53

TAXONOMÍA Y FLORÍSTICABol.Soc.Bot.Méx. 83: 53-76 (2008)

Since the second half of the 20th century, the national strategy for biodiversity conservation in Mexico has

focused largely on the establishment of nature protection areas. Currently, the conservation network of areas under

PLANT DIVERSITY ASSESSMENT IN THE YAXCHILÁN NATURAL MONUMENT, CHIAPAS, MEXICO

JORGE A. MEAVE1, 4, MARCO A. ROMERO-ROMERO1, ANDRÉS VALLE-DOMÉNECH1, 2, ARMANDO RINCÓN-GUTIÉRREZ1, ESTEBAN MARTÍNEZ3 AND CLARA H. RAMOS3

1Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, México 04510, D.F., México.

2Present address: El Colegio de la Frontera Sur, Unidad Villahermosa, Villahermosa, Tabasco, México.3Departamento de Botánica, Instituto de Biología,

Universidad Nacional Autónoma de México, México 04510, D.F, México.4Author for correspondence. E-mail: jorge.meave@ciencias.unam.mx

Abstract: We assessed the diversity of vascular plants in the Yaxchilán Natural Monument, a nature protection area located in Chi-apas State, southern Mexico. A checklist including 547 species (337 genera, 102 families) was produced by combining information derived from three sources: (1) an initial list derived from an ecological study on forest structure; (2) a systematic survey conducted over an 18-month period; and (3) an extra visit to the site as part of a more ambitious project covering the entire Lacandon rain forest region. February was the month in which the largest number of fertile vouchers was collected in two consecutive years. The families with greatest richness were Fabaceae (47 species), Orchidaceae (34), Rubiaceae (23), and Asteraceae (22). The most spe-ciose genera were Piper (13 species), Psychotria (9), Adiantum and Peperomia (8). Trees were the largest growth form group (203 species), followed by terrestrial herbs (129). Most species (459) were encountered in primary, closed forest, but secondary vegeta-tion contributed 125 species. An estimation of the total size of Yaxchilán fl ora obtained through the Chao 2 algorithm indicated that this protected area may host more than 850 plant species. Despite its relatively small area, the Yaxchilán Natural Monument hosts a considerable biodiversity, representing over 16.2% of the recorded fl ora in the entire Selva Lacandona region, and over 7.2% of the State fl ora.Key words: biodiversity assessment, fl oristics, Lacandon rain forest, nature preserve, Usumacinta River, tropical rain forest.

Resumen: Se evaluó la diversidad de plantas vasculares presentes en el Monumento Natural Yaxchilán, un área natural protegida del estado de Chiapas, sur de México. La lista fl orística, que incluye 547 especies (337 géneros y 102 familias) de plantas vasculares, fue elaborada a partir de la compilación de información derivada de tres fuentes: (1) una lista parcial obtenida a partir de un estudio ecológico de la estructura del bosque en una parcela de 1 ha en esta localidad; (2) una exploración sistemática realizada en siete viajes al sitio en un periodo de 18 meses; y (3) una visita extra al sitio como parte de una investigación más ambiciosa que abarca toda la Selva Lacandona. Los mayores números de ejemplares fértiles por visita fueron recolectados en el mes de febrero de dos años consecutivos. Las familias con mayor riqueza de especies fueron Fabaceae (47 especies), Orchidaceae (34), Rubiaceae (23), y Asteraceae (22). Los géneros más ricos en especies fueron Piper (13 especies), Psychotria (9), Adiantum y Peperomia (8). La categoría de forma de crecimiento más grande fue la de los árboles (203 especies), seguido por el de las hierbas terrestres (129). La mayoría de las especies (459) fueron halladas en la vegetación de selva primaria, aunque la vegetación secundaria también tuvo una contribución sustancial (125 especies). Se estimó que el tamaño de la fl ora total en Yaxchilán puede ser de alrededor de 850 espe-cies de plantas, según el procedimiento de Chao 2. A pesar de su tamaño relativamente pequeño, el Monumento Natural Yaxchilán alberga una biodiversidad vegetal considerable, cuyo número representa 16.2% de la fl ora en toda la Selva Lacandona y alrededor de 7.2% de la fl ora conocida para el estado.Palabras clave: área natural protegida, evaluación de la biodiversidad, fl orística, río Usumacinta, Selva Lacandona.

federal protection (known as SINANP, the National System of Protected Areas), which is under the responsibility of the Secretariat of the Environment and Natural Resources (SEMARNAT), encompasses an archipelago of 161 protected

54

MEAVE ET AL.

areas distributed across all ecological zones and in all 31 States plus the Federal District of the country (CONANP, 2008). Based on the recognition of differences in conservation status, degree of human occupancy, size, and other features of the nature preserves, the SINANP comprises a range of categories, including Biosphere Reserves, National Parks, Special Fauna and Flora Protection Areas, and other kinds of areas enjoying offi cial protection. “Natural Monument” (Monumento Natural) is one of these categories, and is de-fi ned in the Mexican Environmental Regulations as any area where protection is justifi ed based on the fact that it contains one or several unique natural components, and a large aes-thetic, historic or scientifi c value. For these reasons they are given the status of absolute protection. Natural Monuments cannot be included in other categories because they lack the variety of ecosystems that usually characterizes them or be-cause they are too small (CONANP, 2008). Despite the importance and the potential benefi ts of this strategy for the conservation of the national fauna and fl ora, a full appreciation of the value, and particularly of

the effi cacy of nature protection areas in protecting the rich biodiversity of Mexico, cannot be fully achieved without having comprehensive inventories for all biological groups that occur and are able to maintain viable populations with-in their limits. In addition, implementation of management programs is required by law for all protected areas within SINANP. However, in the case of several nature protection ar-eas the lack of adequate biological inventories has hindered the making of these management plans. Ultimately, the risk is that the lack of a management plan may trigger some dis-turbing processes that may potentially result in the decline of the biological integrity of the protected area. Considering their small size compared to other nature protection areas included in the SINANP, this is of particular concern in the case of Natural Monuments. The protected status of Yaxchilán began with a Presi-dential Ordinance granted to an area of 2,261 ha on August 24, 1994 (SEDESOL, 1992; Anonymous, 1995). In 1997, a col-laborative study was undertaken in the Yaxchilán Natural Monument (hereafter YNM), in order to provide a com-prehensive assessment of its biological diversity based on

Figure 1. Location and limits of the Yaxchilán Natural Monument, Chiapas State, southern Mexico. Climate diagrams are shown for Yaxchilán as well as for two nearby locations: Bonampak (b) and Agua Azul (c). The middle of the Usumacinta River marks the border between Mexico and Guatemala in this part of the country.

55

PLANT DIVERSITY IN YAXCHILÁN, CHIAPAS, MEXICO

inventory work for several animal groups, as well as for vascular plants (Meave and Luis-Martínez, 1999; Meave, 2008). The ultimate goal of this effort was to provide a com-prehensive evaluation of the biological diversity existing in this area, with the hope that this would serve as the basis for a future management plan. In this paper we provide the fi rst ac-count of the vascular plant diversity of the YNM. The fl oristic checklist presented here adds to those already published for the avifauna (Puebla-Olivares et al., 2002), mammals (Escobedo-Morales et al., 2005), and the herpetofauna (Ferreira-García and Canseco-Márquez, 2006). The list is not limited to the taxonomic information, but also includes data on growth form and the timing of reproductive phenology.

Study site

Location and physical environment. The YNM is located in the State of Chiapas (Ocosingo county, southern Mexico; 16°50’29”-16°54’05” N; 90°56’48”- 91°00’38” W), in the easternmost portion of the region known as Selva Lacandona (Lacandon Rain Forest). The Natural Monument is located on the left bank of the Usumacinta River, at the point where it marks the Mexico-Guatemala border; part of the YNM territory is encircled by a large bend of the river, known as “Yaxchilán’s omega” (fi gure 1). Based on discharge vol-ume, the drainage basin of this river ranks no. 1 in Mexico (de Vos, 1994). At Yaxchilán the Usumacinta fl ows with a SE-NW direction towards the Gulf of Mexico. Predominant surface geology is limestone of Upper Cre-taceous age (SPP, 1981); under the tropical climate a karstic terrain has originated, creating a moderately abrupt land-scape dominated by circular hills, short escarpments and dissolution basins (García-Gil and Lugo-Hupb, 1992; Ali-phat-Fernández, 1996). In the area surrounded by the river’s omega, elevation ranges between 80 and 260 m a.s.l.; fur-ther south, in the portion of the YNM abutting the El Tor-nillo range, maximum elevation is around 320 m. Prevail-ing soils are shallow rendzinas with high clay and organic matter contents in the upper layer; shallow lithosols, less than 10 cm deep and having many rock outcrops also occur (SPP, 1981). Some areas located in low topographic posi-tions are poorly drained and often become fl ooded during the rainy season. This heterogeneity seems to be common in the Selva Lacandona region, where considerable differ-ences in soil depth and associated water retention capacity have been reported between the higher parts of the hills and the intervening lower terrain (Miranda, 1961; Siebe et al., 1996). The Selva Lacandona is a region of high precipitation; water is mostly brought in by the Easterlies after their pas-sage over the Gulf of Mexico. In late summer and early autumn precipitation peaks due to cyclonic disturbances originated both in the Gulf of Mexico and the Pacifi c Ocean. Climate in Yaxchilán is of the Amw”ig type, i.e. the least

humid of tropical humid climates. Mean annual temperature is ca. 25.5(C and total annual precipitation ranges between 1,560 and 2,380 mm (Herbert-Pesquera, 1995), with a mean of ca. 1,950 mm (SPP, 1981). Winter precipitation accounts for over 10% of total annual rainfall (Cardoso-D., 1979).

Vegetation. The Selva Lacandona is the Chiapan portion of a large region, measuring ca. 3 million hectares, that was originally covered by a mosaic of rain and evergreen low-land and montane forests, which is shared between the states of Chiapas and small portions of Campeche and Tabasco in Mexico, and the abutting El Petén department in Guatemala (Martínez et al., 1994; Meave, 1995; Medellín, 1996). The Selva Lacandona is one of the largest rain forest regions in Mexico, and originally it covered nearly one and a half mil-lion hectares. Despite being considered as one of the most important centers of biodiversity in Mexico (de la Maza and de la Maza, 1991; Medellín, 1991; de la Maza, 1998) as a re-sult of the extremely high deforestation rates in the past four decades, the extent of the rain forest has been reduced to less than 500,000 ha (Medellín, 1996), of which 331,200 are protected in the large Montes Azules Biosphere Reserve. Despite a relatively low precipitation for tropical rain forest standards (Whitmore, 1990; Richards, 1996), the impression that vegetation in the YNM gives to fi rst-time visitors is that of a lush, well-developed tropical rain forest. Trees about 50 m in height are common, particularly Ceiba pentandra and Ficus spp. However, after several walking expeditions through the area and a closer inspection of the vegetation, a different perspective is gained, as a considerable heteroge-neity in many vegetation characteristics can be appreciated. The taller vegetation is found in ravines and in the many relatively small valleys that occur throughout the YNM. This widespread community may be classifi ed as tropical evergreen forest (Breedlove, 1973; selva alta perennifolia after Miranda and Hernández-X. [1963], or bosque tropical perennifolio after Rzedowski [1978]). Elsewhere, however, the forest is not so tall; on upper slopes and hilltops the trees are shorter and never reach heights of 25 m, apparently as a consequence of the notably drier environment that results from the shallow soils on these slopes. This shorter commu-nity is also distinguished by a more open canopy, and may be classifi ed as semi-evergreen medium-height forest (selva mediana subperennifolia after Miranda and Hernández-X. [1963] or bosque tropical subperennifolio after Rzedowski [1978]). It is likely that this shorter community has led some authors to classify the Yaxchilán vegetation in general as a medium-height forest (selva mediana) (Aliphat-Fernán-dez, 1996). However, it is clear that the mature vegetation of the YNM should be better described as an intricate mo-saic composed of patches of tall and medium-height forest that respond to topographic and edaphic variation across the landscape. Valle-Doménech (2000) performed a detailed analysis of this variation at the 1-ha level and found that

56

both forest structure and fl oristic composition varies greatly between these two communities. In periodically fl ooded areas located on the banks of the Usumacinta, a further plant community is present that may be classifi ed as riparian or gallery forest. This community occupies a small area but has a distinctly different appear-ance, probably as a consequence of periodic disturbances due to the large seasonal fl uctuations in water levels. Fi-nally, in the area surrounding the research camp built by the National Institute of Anthropology (INAH) near the ar-cheological zone and around the small landing strip existing there, vegetation displays a varying degree of human altera-tion, including one old orchard and some abandoned milpas (traditional maize fi elds). Martínez et al. (1999) listed 13 vegetation types for the entire Selva Lacandona region including several variants and transitions; at a smaller scale, the vegetation occurring in Yaxchilán closely matches this mosaic pattern. From a phy-togeographic perspective, Yaxchilán forms part of the Gulf of Mexico Floristic Province (Rzedowski, 1978); however, Wendt (1993) and Ibarra-Manríquez et al. (2002) consider the areas located in Tabasco, northern Chiapas, and western Campeche as transitional between the Gulf of Mexico and the Yucatan Peninsula fl oristic provinces. As in other marginal rain forest regions, leaf phenology is characterized by a large proportion of trees shedding their leaves during the short dry season. In particularly dry years, the leafl ess period may last until mid June or early July. Again, deciduousness is more conspicuous and of longer duration in those areas where soil is shallower and vegeta-tion is shorter and more open.

Human occupation. A remarkable feature of the YNM is the presence of the remains of an ancient city build by the low-land Maya people. Apparently, the fi rst settlement in Yaxchi-lán took place sometime in the Late Preclassic Period (200 BC-AD 200). By AD 600, Yaxchilán had become a power-ful city-state (García-Moll, 1996), probably assisted by its strategic location on the Usumacinta River, which may have been an important route for trade. Yaxchilán architecture is renowned for its fi ne carved stellae, altars and lintels (Garza and Tommasi, 1987). Like other lowland Maya cities, Yax-chilán was abandoned between 800 and 900 AD, at the time of the Maya classic collapse (García-Moll, 1996). An interesting implication of human occupation of the site is the impact that the expansion of a major urban center such as Yaxchilán may have had on the natural environment. Many scholars have suggested that the abandonment of the classic Maya cities (see Challenger, 1998 for a review) re-sulted from extensive land degradation due to soil erosion from agricultural practices. In contrast, Gómez-Pompa (1993) claims that the productive systems used at that time did not affect soils irreversibly, and that deforestation cannot have been total, as the fast forest recovery could not have

taken place without a multitude of natural or managed vege-tation islands containing the necessary germplasm. The land around Yaxchilán was used for subsistence agriculture, like-ly based on corn, beans and squash polyculture, or for cash or other important crops, such as cotton, cacao and copal (an incense-like resin; Challenger, 1998). After abandonment, the vegetation recovered such that by the 20th Century, the forest structure described in the nearby archaeological zone in Bonampak was indistinguishable from that of in primary tropical forest found elsewhere in the Americas (Meave-del Castillo, 1990). At the time of the European contact between the Ameri-cas and Europe, the Selva Lacandona was inhabited by a few choltí communities that were exterminated by the Spanish conquerors during the late 17th Century (de Vos, 1991, 1996). Thereafter, the region remained almost completely uninhab-ited except for a few Yucatec-Maya speaking groups who had little impact on the natural environment (Nations, 1988). After the discovery of the ancient city of Yaxchilán in the early 19th Century (García-Moll and Juárez-Cossío, 1986), a massive exploitation of precious woods began in the Sel-va Lacandona during the second half of that century. The fl uvial network of the Usumacinta and its tributaries served for transporting large pieces of mahogany (Swietenia macro-phylla) and red cedar (Cedrela odorata) to the ports in the Gulf of Mexico. Several logging camps developed along the Usumacinta and its tributaries; Yaxchilán formed part of the territories leased to timber enterprises until the beginning of the 20th Century (de Vos, 1994), and must have suffered the impact of this activity, although this is uncertain (SEMARNAT, 2003). At present, the community of Frontera Corozal, inhabited by people of the chol ethnic group and located 20 km up-stream, has the largest infl uence on the YNM. The town was founded in 1976, at a time when an aggressive campaign by the Federal Government was taking place to colonize the rain forest border regions of southern Mexico (Diechtl, 1987). Currently, surveillance of the archeological zone and of the entire YNM is carried out by inspectors from Frontera Corozal.

Methods

Three sources of information were combined to prepare the checklist of vascular plants for the YNM. First, a modest set of specimens were collected as part of an ecological study in which heterogeneity of forest structure and composition were assessed in a 1-ha plot located in a central portion of Yaxchilán’s “omega” (Valle-Doménech, 2000), relatively distant from the archeological site. These specimens were collected between October 1996 and June 1997. Second, as part of a large collaborative project, a systematic survey was conducted bimonthly over a 15-month period from Decem-ber 1997 to February 1999. During this time, a minimum of

MEAVE ET AL.

57

three persons visited the site seven times for periods ranging between 8 and 12 days; they systematically walked through most of the territory of the YNM to collect samples. On one occasion, locations that were diffi cult to access in the west-ern end of the preserve were reached by boat. Finally, an additional trip to the site was made in March 2005, as part of a more ambitious fl oristic project covering the entire Lacan-don rain forest region. Plant specimens were preserved by soaking them in a 50:50 alcohol/water solution and transported to the Univer-sidad Nacional Autónoma de México (UNAM) in Mexico City. Species determinations were done by some of the au-thors, but many specialists in several plant groups (listed in table 1) took part in this process. The fi rst voucher collection was deposited at MEXU, the National Herbarium of Mexico hosted at the Institute of Biology (UNAM). Additional sets will be distributed to other herbaria shortly. The species in the checklist are organized according to the Cronquist System (with the modifi cations presented in Brummit, 1992) because of its wide use and comparability. Recent taxonomic revisions were used as authorities for the delimitation of species in some groups (e.g. Pteridophytes: Moran and Riba, 1995; Mickel and Smith, 2004; Lauraceae: Lorea-Hernández, 2002; Orchidaceae: Hágsater et al., 2005; Rubiaceae: Borhidi, 2006). When possible, genera nomen-clature was standardized according to Brummitt (1992). Spe-cies author names follow Brummit and Powell (1992) and Villaseñor (2001); species names of others groups were veri-fi ed in the Tropicos.org (2008) and IPNI (2008) web sites. A smoothed species accumulation curve was constructed through randomization of the numbers of species collected on each trip with the Mao Tau procedure. This analysis used the data from the seven trips forming part of the systematic survey only, and was done with The EstimateS software Ver. 8.0 (Colwell, 2006). The potential total size of the fl ora was obtained with the Chao 2 algorithm, which is based on spe-cies incidence (frequency) among samples. The seven col-lecting dates of the systematic survey were used as samples for this procedure. Incidence-based functions used to esti-mate total species richness usually require larger numbers of samples to guarantee unbiased results; therefore, the estimat-ed total size of Yaxchilán fl ora should be viewed cautiously. An initial evaluation of the conservation status of the fl ora of the YNM was obtained by identifying those species listed in the Mexican Offi cial Norm of endangered species (SEMAR-NAT, 2002). Three categories are recognized in this Norm: threatened, endangered, and subjected to special protection.

Results

A total of 1,152 plant specimens were collected. Addition-ally, 29 species were sighted but it was not possible to ob-tain voucher specimens for them; their names are included in the checklist because their taxonomic identities were cer-

tain. The number of specimens determined to species level was 1,092. This gave a total of 547 species distributed in 337 genera and 102 families (appendix 1). Thus, the speci-mens/species ratio for the fl ora of YNM is slightly larger than 2. Most species (488) were collected during the seven expeditions of the longer systematic survey; the initial set of specimens collected in the 1-ha plot contributed 20 spe-cies, and the fi nal collection trip added 17 more with speci-mens and a further 22 species that were observed but not collected (the lack of specimens for the latter is indicated on the checklist). Flowering and/or fruiting specimens were found through-out the year; nonetheless, the yearly distribution of plants bearing reproductive structures was very irregular. Figure 2 shows the numbers of fertile specimens collected during each collecting expedition of the systematic survey: two peaks are evident, each in the month of February of two consecutive years. More remarkable, however, is the fact that the numbers of species in fl ower or fruit were different between this same month in the two years (132 specimens in 1998 vs. 219 specimens in 1999), despite the fact that col-lecting effort (number of collectors, duration of the trip) was

Institution and nameACH Attila BorhidiIE Francisco Gerardo Lorea HernándezIPN Salvador Acosta CastellanosMBG Charlotte Taylor M.NAU Tina J. AyersUAM-I Adolfo Espejo Serna Ana Rosa López FerrariUAN Rosa Estela González FloresUNAM Juan Pablo Abascal Jorge Calónico Soto Fernando Chiang Cabrera Ricardo de Santiago Gómez Nelly Diego Pérez Gabriel Flores Franco Abisaí García Guzmán María Teresa Germán Ramírez Carlos Gómez Hinostrosa Beatriz González Hidalgo

Table 1. List of persons who contributed with plant determinations, arranged by institution. Acronyms: ACH = Academy of Sciences of Hungary, IE = Instituto de Ecología, A.C., IPN = Instituto Politécnico Nacional, MBG = Missouri Botanical Garden, NAU = North Arizona University, UAM-I = Universidad Autónoma Metropolitana - Iztapa-lapa, UAN = Universidad Autónoma de Nayarit, UNAM = Universi-dad Nacional Autónoma de México, and UNO = University of New Orleans.

UNAM (continued) Martha Gual Díaz Lucio Lozada Pérez Patricia Magaña Rueda Juan Martínez Cruz Martha Martínez Gordillo Esteban Martínez Salas Jorge Meave del Castillo Juan Carlos Montero Eduardo Alberto Pérez García Armando Ponce Vargas Angélica Ramírez Roa Clara Hilda Ramos Álvarez Armando Rincón Gutiérrez Marco A. Romero Romero Gerardo Adolfo Salazar Chávez Jorge Sánchez Ken Miguel Ángel Soto Arenas Mario Sousa Sánchez Oswaldo Téllez Valdés Leticia Torres Colín Andrés Valle Doménech Ernesto Velásquez Montes José Luis Villaseñor RíosUNO John F. Utley

PLANT DIVERSITY IN YAXCHILÁN, CHIAPAS, MEXICO

58

almost identical. In contrast, October yielded the smallest number of fertile specimens with 57 species. Fabaceae was the richest family, both by number of genera (28) and species (39) (table 2). Even so, this family only accounted for a relatively small percentage of the total re-corded fl ora (7.6%). The family Orchidaceae was the sec-ond-richest family, both by genera (22) and species (34). While the Rubiaceae and the Asteraceae provided compa-rable species richness (23 and 22 species respectively), the Asteraceae had greater richness at the genus level (19) than the Rubiaceae (13). Other notable families contributing to species richness were Piperaceae (19, but only 2 genera),

Family No. of species No. of genera

Fabaceae 47 29

Orchidaceae 34 22

Rubiaceae 23 13

Asteraceae 22 19

Piperaceae 21 2

Euphorbiaceae 19 13

Poaceae 15 12

Sapindaceae 15 7

Moraceae 14 8

Pteridaceae 12 4

Bignoniaceae 11 7

Araceae 11 5

Bromeliaceae 11 5

Solanaceae 11 4

Acanthaceae 10 8

Tiliaceae 10 6

Table 2. Families with the largest species richness in the fl ora of the Yaxchilán Natural Monument. The number of genera is also shown for these families.

Genus No. of species

Piper 13

Psychotria 9

Adiantum 8

Peperomia 8

Tillandsia 7

Asplenium 6

Heliconia 6

Maxillaria 6

Serjania 6

Ipomoea 5

Pouteria 5

Solanum 5

Table 3. The genera with the largest species richness in the fl ora of the Yaxchilán Natural Monument (Chiapas, Mexico). Shown are all genera having fi ve species or more in this fl ora.

Euphorbiaceae (18 species, 13 genera), Sapindaceae (15 species, 7 genera), and Poaceae (15 species, 12 genera). On average, each family in the fl ora of the YNM is represented by 5.18 species and each genus by 1.56 species. Among the three most species-rich genera there were two belonging to the Piperaceae family (Piper, 11 species, and Peperomia, 8 species), and Psychotria (Rubiaceae) with 9 species. Table 3 lists all genera with fi ve species or more in the fl ora of the YNM. We classifi ed all species collected in seven growth-form categories (fi gure 3). With 203 species, the category of trees was the best represented, but even this group accounted for a mere 37.1% of the total recorded fl ora. Ceiba pentandra is by far the most remarkable species due to its enormous heights (up to 50 m) and its abundance on the river banks, but other common canopy tree species are Ampelocera hot-tlei, Brosimum alicastrum, Manilkara zapota, Pouteria sa-pota and Terminalia amazonia. Beneath these trees, a large group of subcanopy tree species include Guarea glabra, Quararibea funebris, Sebastiania longicuspis, Stemmadenia donnell-smithii and Trichilia erythrocarpa. Finally, a well-represented group of short trees includes Rinorea hummelii, which is present in high density, but Chionanthus oblan-ceolatus, Garcinia macrophylla, Mouriri myrtilloides and Trichilia pallida are also common. The group of terrestrial herbs was the second largest growth-form category, with 129 species (23.6%). These plants are poorly represented in the forest but common in places where vegetation has been disturbed. Common ex-amples are several ferns (Adiantum spp., Asplenium spp., Ctenitis melanosticta, Hemionitis subcordata and Tectaria heracleifolia), as well as other forbs such as Aeschynomene

Figure 2. Number of specimens with fl owers or fruits collected in the Yaxchilán Natural Monument (Chiapas, Mexico) in seven trips from December 1997 to February 1999.

MEAVE ET AL.

59

americana, Costus pictus, Cyperus spp., Lasiacis divarica-ta, Oplismenus compositus, Porophyllum punctatum, Rene-almia mexicana and Tradescantia zanonia. Epiphytic herbs were represented by an intermediate number of species (72, 13.2%; fi gure 3). Among them, spe-cies of the Orchidaceae and Bromeliaceae were the most common, but there are also noteworthy ferns, Araceae and Piperaceae, particularly of the genera Aechmea, Anthurium, Epidendrum, Maxillaria, Oncidium, Peperomia, Polypo-dium, Scaphyglottis and Tillandsia. The remaining groups of growth-forms combined, name-ly climbing herbs, shrubs, and lianas made a smaller and similar contribution to total richness. Examples of the herbs (45 species, 8.2%) include Dalechampia cissifolia, Matelea gentlei and Merremia umbellata; among the most conspicu-ous shrubs (45 species, 8.2%) are the following: Acalypha diversifolia, Critonia belizeana, Deherainia smaragdina, Justicia brevifl ora, Piper spp. and Psychotria limonen-sis. Common lianas (44 species, 8%) include Arrabidaea podopogon, Combretum fruticosum, Mascagnia vaccini-ifolia, Mikania leiostachya, Piptocarpha chontalensis and Tetracera volubilis. The group of palms was represented by nine species only (1.7%), but they are worth mentioning because of their abundance. Particularly conspicuous palms belong to the Chamaedorea genus (C. elegans, C. ernesti-augusti, C. oblongata and C. tepejilote), although Attalea cohune, Cryosophila stauracantha and Geonoma interrupta are also common (A. cohune, a tall arborescent palm, is locally known as ‘corozo’, giving the name to the nearby commu-nity Frontera Corozal). Many of the components of the fl ora of Yaxchilán show clear habitat preferences. The tall tropical rain forest located in deep soils was the vegetation type where the majority of specimens (896) were collected, and in which the larg-

est number of species (459) occurred. This species subset in-cludes, among other common species, the following: Alibertia edulis, Ampelocera hottlei, Bactris mexicana, Chionanthus oblanceolatus, Cryosophila stauracantha, Cymbopetalum pendulifl orum, Dendropanax arboreus, Dialium guianense, Dieffenbachia oerstedii, Dracaena americana, Erythrina chiapasana, Faramea occidentalis, Garcinia macrophylla, Geonoma interrupta, Heliconia vaginalis, Licania platy-pus, Luehea seemannii, Mabea occidentalis, Mesadenella petenensis, Miconia impetiolaris, Mouriri myrtilloides, Nectandra martinicensis, N. salicifolia, Neea psychotrioi-des, Neomarica variegata, Pouteria durlandii, P. sapota, Pseudolmedia spuria, Psychotria chiapensis, P. limonensis, Pterocarpus rohrii, Rinorea hummelii, Simira lancifolia, Strychnos tabascana, Swartzia cubensis, Terminalia ama-zonia, Trichilia pallida, Tropidia polystachya, Vatairea lun-dellii and Vriesea heliconioides. In contrast, a smaller group of species tended to occur on the hilltops with shallower soils, where the environment is generally drier: Aspido-sperma megalocarpon, Chamaedorea elegans, Epidendrum ciliare, Manilkara zapota, Maxillaria aciantha, Mormolyca ringens, Ouratea lucens, Pimenta dioica, Randia aculeata, Trichilia minutifl ora, Vitex gaumeri, Voyria parasitica and V. tenella. Despite the relatively small area occupied by secondary vegetation in the YNM, 171 specimens representing 125 spe-cies were collected in this habitat. Many of these taxa live in fallows left by very limited agricultural activities in the recent past. Common species typical of the secondary veg-etation include Acalypha diversifolia, Alchornea latifolia, Artocarpus altilis*, Attalea cohune, Bixa orellana, Bursera simaruba, Carica papaya, Cecropia peltata, Celtis igua-naea, Cnidoscolus multilobus, Costus pictus, Croton nitens, Dalechampia cissifolia, Delonix regia*, Desmoncus orthac-anthos, Dioscorea bartlettii, Hamelia rovirosae, Heliocar-pus americanus, H. mexicanus, Inga pavoniana, Iresine arbuscula, Mangifera indica*, Mikania leiostachya, Mucu-na argyrophylla, Muntingia calabura, Piper yzabalanum, Plumeria rubra, Sapium laterifl orum, Schizolobium parahyba, Stemmadenia donnell-smithii, Terminalia catappa*, Tetracera volubilis, Thevetia ahouai, Trichospermum grewiifolium, T. mexicanum, Trophis racemosa and Zuelania guidonia. (This group includes several introduced species, marked with an asterisk on this list.) Similarly, those areas of highly-dis-turbed vegetation, namely the INAH camp and the small landing strip, contain a large group of species that thrive in these habitats, most notably Adelia barbinervis, Canna in-dica, Coix lacryma-jobi, Corchorus siliquosus, Desmodium scorpiurus, Heliotropium procumbens, Ipomoea quamo-clit, Merremia umbellata, Muntingia calabura, Notylia aff. barkeri, Oplismenus compositus, Paspalum conjugatum, P. paniculatum, Piper fraguanum, Rhynchosia precatoria, Rivina humilis, Sinclairia deamii, Solanum americanum and Vigna vexillata.

Figure 3. Distribution of species collected in the Yaxchilán Natu-ral Monument (Chiapas, Mexico) among growth form categories. Abbreviations: T = tree; H = terrestrial herb; EH = epiphytic herb; CH = climbing herb; L = liana; S = shrub; P = palm.

PLANT DIVERSITY IN YAXCHILÁN, CHIAPAS, MEXICO

60

The archeological zone, where the ancient buildings of the Mayan city are located, hosts an interesting combina-tion of primary species as well as others typical of habitats with human disturbance. Among the most common ones, all likely to be encountered during a short visit to the zone, are Aechmea bracteata, Alchornea latifolia, Alseis yucata-nensis, Aphelandra scabra, Asplenium cristatum, Brosimum alicastrum, Bursera simaruba, Castilla elastica, Cecropia peltata, Cedrela odorata, Ceiba pentandra, Chamissoa altissima, Coussapoa oligocephala, Dioscorea composita, Dorstenia contrajerva, Erythrina chiapasana, Hamelia ro-virosae, Inga belizensis, Iresine arbuscula, Koanophyllon pittieri, Lasiacis divaricata, Leochilus scriptus, Maxillaria hedwigae, Nidema boothii, Peperomia nigropunctata, P. ob-tusifolia, Piper auritum, Protium copal, Pseudobombax el-lipticum, Quararibea funebris, Rhipsalis baccifera, Ruellia pereducta, Spondias mombin, Stemmadenia donnell-smithii, Tillandsia schiedeana and Trichilia erythrocarpa. The banks of the Usumacinta River provide habitats for plant species that are normally absent from forest vegeta-tion with a closed canopy. These areas are particularly het-erogeneous because some portions are regularly fl ooded during the rainy season, whereas others are only inundated infrequently, although all are subjected to disturbance by the river. Despite this heterogeneity, the narrow gallery forest contributed little to the fl ora of the YNM (four species, com-pared to the 19 species that were collected on the beaches that form during the low water period of the dry season along the Usumacinta River). Some conspicuous species of these envi-ronments are Amphitecna apiculata, Ceiba pentandra, Cype-rus odoratus, Eragrostis hypnoides, Euphorbia hyssopifolia, Ficus glabrata, Guadua longifolia, Inga vera, Ludwigia lep-tocarpa, Mimosa pigra and Muntingia calabura. While many species occurred in two vegetation types,

only two species (Malvaviscus arboreus var. mexicanus and Cissus verticillata subsp. verticillata) occurred in three hab-itats (primary rain forest, secondary vegetation, and riparian habitats along the Usumacinta). For Yaxchilán, as for any other protected area, the mag-nitude of biodiversity is an important question. Based on species collected during the systematic survey (fi gure 4), neither the observed nor the estimated cumulative species/area curve (based on the Mau Tao procedure) showed a clear stabilization, suggesting that they would have continued to increase with additional collecting effort. The Chao 2 esti-mator, which is calculated based on information on species occurrence in the samples (the collecting trips), produced an estimated mean richness of 855.8 species (95% C.I. = 760.0 to 985.2). The mean value exceeds the observed richness by more than 56%. According to the Mexican Norm of endangered taxa (SEMARNAT, 2002), two species occurring in the YNM are classifi ed as requiring special protection (Pr): Tillandsia festucoides (Bromeliaceae), and Hamelia rovirosae (Ru-biaceae). In turn, nine species are classifi ed as threatened: two understorey palms (Chamaedorea ernesti-augusti and Cryosophila stauracantha), two Araceae (Dieffenbachia oerstedii and Monstera tuberculata), one Euphorbiaceae (Tetrorchidium rotundatum), one Clusiaceae (Calophyllum brasiliense), one Anacardiaceae (Astronium graveolens), one Acanthaceae (Bravaisia integerrima), and one Asplenia-ceae (Asplenium serratum). Finally, one canopy tree species (Vatairea lundellii, Fabaceae) is considered to be in danger of becoming extinct. The number of taxa in this set (12 spe-cies) implies that only 2.2% of the fl ora of the YNM has re-ceived a protection status according to Mexican legislation.

Discussion

In agreement with its defi nition of Natural Monument, the protected area of Yaxchilán is very small (just over 2,600 ha) in comparison to other protected areas included in the SINANP in Mexico, but also in comparison to many protected areas worldwide. Therefore, it is remarkable that this small protected area harbors a considerable plant diversity that encompasses almost 550 species of vascular plants. This fi gure is equivalent to 16.2% of the known fl ora (3,400 spe-cies) for the Selva Lacandona region (Martínez et al., 1994), and 7.2% of the more than 7,600 species enlisted by Breed-love (1986) for the entire State of Chiapas, one of the most diverse states in the country (Breedlove, 1973). The botani-cal information provided by this study agrees with the high levels of diversity recorded for other biological groups (235 bird species; Puebla-Olivares et al., 2002; 70 mammals spe-cies; Escobedo-Morales, 2005; 14 amphibian and 41 reptilian species; Ferreira-García and Canseco-Márquez, 2006). The magnitude of the fl ora of YNM is equivalent to that recorded in Bonampak, one of the two other Natural Monu-

Figure 4. Species accumulation curves in the seven fi eld trips to the Yaxchilán Natural Monument (Chiapas, Mexico). The ob-served curve follows the temporal sequence of the fi eld trips. The smoothed cumulative curve is based on the calculated numbers of species with the Mao Tau procedure (see text for details). Error bars = 95% C.I.

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ments forming part of SINANP in Mexico. Meave-del Castillo (1990) reported 470 plant species for Bonampak, an area located less than 15 km from Yaxchilán, separated by the low elevation Cojolita range that divides the basins of the Lacanjá and Usumacinta rivers. The taxonomic information for Bonampak may be out of date, and a revision of the fl ora may be warranted to assess the degree of overlap and com-plementarity between these two well-preserved rain forest areas. At present it is impossible to make a precise comparison of the size of the fl ora of the YNM with that of its enormous neighboring Montes Azules Biosphere Reserve, which covers an area larger than 330,000 ha (i.e. more than 127 times the size of the YNM); however, some data are avail-able that allow an initial comparison. Castillo-Campos and Narave-Flores (1992) published a checklist including 984 species (distributed in 116 families) of vascular plants that were collected in eight localities spread over a large area of the Montes Azules Biosphere Reserve, all located along the Lacantún River and some of its major tributaries, or ad-jacent to lakes occurring in the reserve. Although these au-thors do not provide any indication of collecting effort, it is interesting that the known number of species for Yaxchilán is equivalent to 55.6% of the fi gure reported by them. It must be acknowledged, however, that the YNM is by no means the richest tropical rain forest protected area in Mexico of equivalent size. In the Los Tuxtlas Biological Re-serve (ca. 600 ha), located in Veracruz State, updated botan-ical information confi rms the occurrence of 860 species of Magnoliophytes distributed in 506 genera and 119 families (Ibarra-Manríquez and Sinaca-Colín, 1997), plus 80 species of Pteridophytes sensu lato (Riba and Pérez-García, 1997), totaling 940 species of vascular plants. The difference in species richness between Yaxchilán and Los Tuxtlas likely also results from a much longer period of botanical explora-tion at the latter location (covering at least a couple of de-cades). Nonetheless, the difference may also be accounted for by the disparity in precipitation between the two regions: the Los Tuxtlas reserve receives an average precipitation of over 4,500 mm yearly, approximately 2.3 times that of the YNM. With a mean annual precipitation less than 2,000 mm, the climate of Yaxchilán is classifi ed as wet seasonal (Walsh, 1996), which suggests that species with very high humidity requirements may be excluded from the forest, and in turn that many species present are more drought tol-erant than most typical rain forest plants. These possibilities remain to be investigated. It is also clear that the number of plants species in the YNM has not been fully tallied. The fi rst indication of a larger fl ora for this site is the Chao 2 algorithm, which pro-duced an estimated mean richness of 855.8 species, a fi gure similar to the known fl ora of Los Tuxtlas. Second, most of the fi eld work was conducted in 1998 when a severe drought caused by a particularly strong El Niño event affected the

southern part of Mexico, including the Yaxchilán region. In that year, a reduction in fl owering intensity in Chajul was observed (S. Sinaca, com. pers.), a locality further south in Chiapas with a much larger annual precipitation than Yax-chilán. It is likely that this climatic event had a consider-able negative impact; by causing a more intense water stress than usual during the period in which the fl owering peak in this region takes place (February to May). In fact, the differ-ences in number of fl owering and fruiting species between February 1998 and February 1999 could be a further indica-tion that 1998 was particularly dry. In regions marginal for rain forest development, as is the case of Yaxchilán, occa-sional very dry years may strongly limit the occurrence of species with very high water requirements (Jacobs, 1988); therefore, keeping adequate climatic records in the future may be very important to gain a better insight on the rich-ness and fl oristic composition of the YNM. Moreover, it cannot be denied that there was some bias in collecting plant specimens. A considerable effort was devoted to the collection of tree specimens; however, this bias may not have compensated for the very low densities of some tree species that are typical in rain forests, and, in fact, for many tree species only a single individual was en-countered. However, the fi gure corresponding to trees in the YNM (203) is comparable to the 194 species reported by Ochoa-Gaona and Domínguez-Vázquez (2000) for Chajul, also in the Lacandon region. In Yaxchilán, terrestrial herbs richness ranked second, probably because they are easy to collect. In Chajul, however, shrubs (126 species) ranked second, greatly outnumbering the fi gure observed in the YNM; therefore, future botanical exploration in this reserve should pay more attention to this growth form. Also, more specimens were obtained both in areas of primary and dis-turbed vegetation in the vicinity of the archeology camp and much less time was allocated for the exploration of the most distant areas of the YNM, which are further away from the river. Additionally, limited access to the forest canopy (even though climbing gear was used to reach many canopy trees) may have concealed a considerable proportion of the epiphytic plants occurring in the area. A similar situation may be true for lianas, as derived from the contrast between the fi gure obtained for the YNM (45) and those reported by Ochoa-Gaona and Domínguez-Vázquez (2000) and Solór-zano et al. (2002) for Chajul (72 and 128, respectively). In contrast, palms are very conspicuous elements of the fl ora and are likely very well represented in the checklist. These considerations highlight the need to continue the botanical exploration in Yaxchilán, paying particular attention to the canopy and the least accessible parts of the protected area. An important criterion in assessing the protecting effi -cacy of the YNM for threatened plant species is the number of taxa included in the Mexican Norm. The small number of species (12) of the fl ora of the YNM that is listed in this environmental legal instrument may actually under-rep-

PLANT DIVERSITY IN YAXCHILÁN, CHIAPAS, MEXICO

62

resent the risk situation in the fl ora of Yaxchilán; for ex-ample, there are many typical primary forest species that are practically absent from the large areas of the Lacandon Forest where vegetation has been altered or removed for agriculture and livestock, which are threatened by habitat destruction but not mentioned in the Offi cial Norm. That is the case, among others, of Cojoba arborea (Mimosaceae), Dracaena americana (Agavaceae), Myroxylon balsamum (Fabaceae), Terminalia amazonia (Combretaceae), as well as several orchid species. In addition, there is at least one species (Swietenia macrophylla) that deserves special pro-tection, given the need to maintain a diverse germplasm for an economically important tree species that for a long time was important in the economy of the tropical humid regions of Mexico (González-Pacheco, 1983; de Vos, 1991, 1994), and that is slowly gaining a new impulse through the estab-lishment of plantations. The evaluation of the potential for biological conserva-tion in the YNM should not be constrained to its role in pro-tecting different groups of species, but should also consider its capability to preserve particular habitats or whole eco-logical systems. González-Espinosa et al. (2005) provided a classifi cation for the entire State of Chiapas in which 10 environmental groups were distinguished. Yaxchilán is lo-cated in the area corresponding to Environmental Group V, which is mostly distributed in the Lacandon Forest region, particularly within the Usumacinta River basin. Large ar-eas of this region are presently deforested, especially in the Marqués de Comillas sector, and therefore the YNM pro-vides an excellent opportunity to maintain at least a mini-mum representation of this environmental group. The fl oristic survey reported here for the YNM confi rms the large biological diversity that is being protected in this conservation unit. The present assessment, however, is in-suffi cient, as the challenge is to maintain such large bio-diversity in the future. By comparing land use/land cover changes within Mexican biological reserves and equivalent areas around them, Figueroa and Sánchez-Cordero (2008) found that the YNM has been an effective protection area since its creation, in contrast to many other areas of the SIN-ANP. In the Lacandon Forest region this is particularly im-portant, as it has been demonstrated that the intensifi cation of the slash-and-burn agriculture system, still practiced in this region, results in a continuous impoverishment of the local biological systems (Ochoa-Gaona et al., 2007). Every effort must be made to maintain the high effectiveness. In this context, it is critical that a legal management plan for the YNM is developed soon that will provide a legal frame-work to regulate human activities in Yaxchilán.

Acknowledgements

We thank the authorities of the Frontera de Corozal com-munity for granting us permission to carry out this study

in Yaxchilán; the assistance and hospitality of many people of this community is warmly acknowledged. The National Commission for Biodiversity in Mexico (CONABIO) provided funds to carry out most of the fi eld work in Yaxchilán (grant no. FB443/M099/97). We are grateful to the National In-stitute of Anthropology and History (INAH) for all the as-sistance provided, as well as for the permission to use their facilities at the archeological zone; we are particularly in-debted to Mario Pérez Campa and Aidée Orea Magaña for their encouragement. Carlos Anaya, Liliana López, Efraín Tovar and Irene Sánchez-Gallen assisted in fi eldwork. Con-tinuous logistic support was provided by Manuel Pérez García, Marcos Cruz Díaz, Agustín López Arcos, Felipe Arcos Díaz, Gabriel Aguilar Méndez and Demetrio Álvarez Montejo. Collecting permits were provided by the Instituto Nacional de Ecología. Trudy Kavanagh kindly proof-read a previous version of this paper and improved our English. We express our gratitude to all plant specialists listed in table 1 for kindly providing and revising plant determinations; the taxonomic accuracy of our checklist depends very much on their generous collaboration.

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Medellín R.A. 1991. La fauna: diversidad de los vertebrados. In: Anonymous. Lacandonia: el Último Refugio, pp. 75-109, Uni-versidad Nacional Autónoma de México, Mexico City.

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Received: August 22, 2008Accepted: October 6, 2008

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LYCOPODIOPSIDASelaginellaceaeSelaginella mickelii Valdespino AR-840, MR-3302 (herb; t)Selaginella umbrosa Lem. ex Hieron. MR-3444 (herb; t)

POLYPODIOPSIDAAspleniaceaeAsplenium abscissum Willd. LO-001 (herb; t; ft: Oct)Asplenium barbaense Hieron. JM-2096 (herb; t; ft: Feb)Asplenium cristatum Lam. MR-3341, 3547 (herb; t; ft: Feb)Asplenium hoffmannii Hieron. JM-2180 (herb; t; ft: Feb)Asplenium monodon Liebm. MR-3311 (epiphytic herb; t; ft: Dec)Asplenium serratum L. MR-3545 (herb; t; ft: Feb)

DavalliaceaeNephrolepis pendula (Raddi) J.Sm. MR-3350 (epiphytic herb; t; ft: Feb)

LomariopsidaceaeBolbitis portoricensis (Spreng.) Hennipman MR-3416 (herb; t; ft: Apr)Lomariopsis recurvata Fée MR-3471 (epiphytic herb; t; ft: Aug)

PolypodiaceaeCampyloneurum xalapense Fée AR-821, 857, MR-3332, 3537 (epiphytic herb; t; ft: Feb: Dec)Niphidium crassifolium (L.) Lellinger MR-3384 (epiphytic herb; t; ft: Apr)Polypodium cryptocarpon Fée AR-827 (epiphytic herb; t; ft: Dec)Polypodium fraternum Schltdl. et Cham. AR-856 (epiphytic herb; t; ft: Dec)Polypodium hispidulum Bartlett MR-3320 (epiphytic herb; t; ft: Dec)Polypodium polypodioides (L.) Watt var. polypodioides AV-218 (epiphytic herb; t; ft: Jun)

PteridaceaeAdiantum amplum C.Presl MR-3573 (herb; t; ft: Feb)

Appendix 1: Checklist of vascular plants of the Yaxchilán Natural Monument, Chiapas (Mexico). For each species the name(s) of the collector(s) and collecting number(s) of vouchers deposited at the National Herbarium of Mexico (MEXU) are given. Abbre-viations and keys: AV = Andrés Valle-Doménech, AR = Armando Rincón-Gutiérrez, EM = Esteban Martínez-Salas, LO = Liliana I. López-Olmedo, JM = Jorge A. Meave, MR = Marco A. Romero-Romero, Obs = species that were observed, easily recognizable to species but that could not be collected. Within brackets the following information is included: growth form, vegetation type [t = tropical rain forest, s = secondary vegetation, r = riparian vegetation, b = beach vegetation on the Usumacinta river]. Finally, the months in which specimens were collected are indicated; ft = fertile fronds (for ferns); fl = fl ower, fr = fruit. Lack of this informa-tion indicates that the specimen was collected in sterile condition.

Adiantum latifolium Lam. EM-37422 (herb; t; ft: Mar)Adiantum macrophyllum Sw. MR-3484 (herb; t; ft: Oct)Adiantum pulverulentum L. MR-3340, 3349 (herb; t; ft: Feb)Adiantum tenerum Sw. AR-841 (herb; t; ft: Dec)Adiantum tetraphyllum Kunth AV-007 (herb; t)Adiantum wilesianum Hook. AR-837 (herb; t; ft: Dec)Adiantum wilsonii Wook. JM-2209, MR-3331, 3394 (herb; t; ft: Feb, Apr)Hemionitis subcordata (D.C.Eaton ex Davenp.) Mickel AR-839, MR-3300, 3585 (herb; t)Pityrogramma calomelanos (L.) Link var. calomelanos JM-2266 (herb; t; ft: Feb)Pteris altissima Poir. JM-2100 (herb; t; ft: Feb)Pteris longifolia L. MR-3479, 3501 (herb; t; ft: Feb)

SchizaeaceaeLygodium venustum Sw. MR-3307, 3335 (climbing herb; t; ft: Feb)

TectariaceaeCtenitis melanosticta (Kunze) Copel. AV-145 (herb; t; ft: Feb)Tectaria heracleifolia (Willd.) Underw. AR-838, AV-041, MR-3301, 3303, 3315, 3357 (herb; t; ft: Feb, Dec)Tectaria incisa Cav. JM-2189 (herb; t; ft: Feb)Tectaria mexicana (Fée) C.V.Morton AR-875, JM-2099 (herb; t; ft: Feb, Dec)

VittariaceaeAnanthacorus angustifolius (Sw.) Underw. et Maxon MR-3326 (epiphytic herb; t; ft: Dec)

WoodsiaceaeDiplazium vera-pax (Donn.Sm.) Hieron. AR-874, JM-2097 (herb; t; ft: Feb, Dec)

LILIOPSIDAAgavaceaeDracaena americana Donn.Sm. AR-956, AV-034, MR-3344 (tree; t; fr: Feb, Nov)

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AraceaeAnthurium crassinervium (Jacq.) Schott JM-2083 (epiphytic herb; s; fl : Feb; fr: Feb)Anthurium pentaphyllum (Aubl.) G.Don var. bombacifolium (Schott) Madison MR-3316 (epiphytic herb; s; fl : Dec)Anthurium schlechtendalii Kunth AR-1034 (epiphytic herb; t; fr: Aug)Anthurium sp. AR-877 (herb; t; fr: Dec)Dieffenbachia oerstedii Schott AR-1027 (herb; t; fr: Aug)Monstera acuminata K.Koch Obs-EM-01 (epiphytic herb; t)Monstera tuberculata Lundell AR-923, AV-191, MR-3448 (epiphytic herb; s; fl : Feb; fr: Feb, Jun, Aug)Philodendron warszewiczii K.Koch et C.D.Bouché AV-288 (epiphytic herb; s; fl : Feb)Syngonium macrophyllum Engl. AV-251, MR-3318, 3319 (epiphytic herb; s; fl : Dec; fr: Aug, Dec)Syngonium podophyllum Scholt AV-289 (epiphytic herb; s; fl : Feb)Syngonium schottianum Wendl. ex Schott JM-2212 (climbing herb; t; fl : Feb)

ArecaceaeAttalea cohune Mart. JM-2211 (palm; t)Bactris mexicana Mart. AV-110 (palm; t; fl : May; fr: May)Cryosophila stauracantha (Heynh.) R.Evans AR-979, AV-075, 261 (palm; t; fl : Aug; fr: Feb, Apr)Chamaedorea elegans Mart. AR-1054, AV-024, 037, 113, EM-37476, MR-3467 (palm; t; fl : Mar, Oct, Nov; fr: May, Aug, Oct)Chamaedorea ernesti-augusti H.Wendl. AR-890, 896, AV-011, 011bis, 036, MR-3381, 3492, 3493 (palm; t; fl : Feb, Apr, Nov; fr: Feb, Oct)Chamaedorea oblongata Mart. AR-895, AV-006, 027, 088, MR-3380, 3412, 3468 (palm; t; fl : Apr; fr: Feb, Apr, Aug, Oct)Chamaedorea tepejilote Liebm. ex Mart. AR-932, 1044, AV-035, 108, 148 (palm; t; fr: Feb, Apr, May, Aug, Nov)Desmoncus orthacanthos Mart. MR-3430 (climbing palm; t; fr: Jun)Geonoma interrupta Mart. AV-093, 312 (palm; t; fl : Feb; fr: Feb)

BromeliaceaeAechmea bracteata (Sw.) Griseb. AR-880, 976, (epiphytic herb; t; fl : Apr, Dec; fr: Dec)Aechmea tillandsioides (Mart. ex Schult. et Schult.f.) Baker AR-846 (epiphytic herb; t)Androlepis skinneri Brong. ex Houllet Obs-EM-02 (epiphytic herb; t)

Catopsis nutans Baker AR-965 (epiphytic herb; t; fr: Apr)Tillandsia caput-medusae E.Morren AR-858 (epiphytic herb; t; fl : Dec)Tillandsia festucoides Brongn. ex Mez MR-3348 (epiphytic herb; t)Tillandsia fi lifolia Schltdl. et Cham. MR-3352 (epiphytic herb; t; fr: Feb)Tillandsia juncea (Ruiz et Pav.) Poir. AR-863 (epiphytic herb; t; fl : Dec)Tillandsia polystachia (L.) L. EM-37455 (epiphytic herb; t; fl : Mar)Tillandsia schiedeana Steud. AR-907, 935, EM-37443 (epiphytic herb; t; fl : Mar, Apr; fr: Feb, Apr)Tillandsia variabilis Schltdl. AV-279 (epiphytic herb; s; fl : Feb)Vriesea heliconioides (Kunth) Hook. ex Walp. AV-322, MR-3343, 3472 (epiphytic herb; t; fl : Aug; fr: Feb)

CannaceaeCanna indica L. AR-844, EM-37436 (herb; t; fl : Dec; fr: Mar, Dec)

CommelinaceaeGibasis geniculata (Jacq.) Rohw. AV-166 (climbing herb; t; fl : Feb)Tradescantia huehueteca (Standl. et Steyerm.) D.R.Hunt MR-3541 (herb; t; fl : Feb)Tradescantia zanonia (L.) Sw. LO-011, MR-3453 (herb; t; fl : Aug; fr: Nov)Tripogandra grandifl ora (Donn.Sm.) Woodson AR-892, AV-164, 313, JM-2246 (climbing herb; t, s; fl : Feb)

CostaceaeCostus pictus D.Don AR-1036, JM-2264 (herb; t; fl : Aug)Costus scaber Ruiz et Pav. JM-2220 (herb; t; fl : Feb)

CyperaceaeCyperus imbricatus Retz. AV-219 (herb; b; fl : Jun)Cyperus ligularis L. AV-220 (herb; b; fl : Jun)Cyperus odoratus L. AV-182 (herb; t)

DioscoreaceaeDioscorea bartlettii C.V.Morton MR-3327, 3549 (climbing herb; t; fr: Feb)Dioscorea composita Hemsl. JM-2224, 2271 (climbing herb; t; fr: Feb)Dioscorea densifl ora Hemsl. MR-3481, 3542, 3564, 3566 (climbing herb; t; fl : Oct, Feb)

HeliconiaceaeHeliconia adfl exa Standl. AV-038, 141 (herb; t; fl : Nov)

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Heliconia aurantiaca Ghiesbr. AV-307 (herb; s; fl : Feb)Heliconia latispatha Benth. AR-845 (herb; t; fr: Dec)Heliconia psittacorum L.f. AV-090 (herb; t; fl : Feb)Heliconia spissa Griggs EM-37441 (herb; t; fl : Mar)Heliconia vaginalis Benth. AR-876 (herb; t; fl : Dec)

IridaceaeEleutherine bulbosa (Mill.) Urb. LO-016 (herb; t; fl : Nov)Eleutherine latifolia (Standl. et L.O.Williams) Ravenna AV-066 (herb; t)Neomarica variegata (M.Martens et Galeotti) Henrich et Goldblatt AV-015, 111 (herb; t; fl : May; fr: Oct)

LiliaceaeHymenocallis littoralis (Jacq.) Salisb. AR-888, MR-3572 (herb; b; fl : Feb)Sprekelia formosissima (L.) Herb. AR-960 (herb; s; fl : Apr)

MarantaceaeCalathea macrosepala K.Schum. MR-3474 (herb; s; fl : Oct)

OrchidaceaeAnathallis sertularioides (Sw.) Pridgeon et M.W.Chase JM-2260 (climbing herb; t)Anathallis yucatanensis (Ames et C.Schweinf.) R.Solano et Soto Arenas AR-850 (epiphytic herb; t)Brassia caudata (L.) Lindl. AR-885bis AV-067 (epiphytic herb; t; fl : Feb, Dec)Encyclia alata (Bateman) Schltr. JM-2261 (epiphytic herb; t)Epidendrum cardiophorum Schltr. AR-853, 1026, 1055, AV-130, JM-2272, MR-3454, 3497 (epiphytic herb; t, s; fl : Aug, Nov, Dec; fr: Feb)Epidendrum ciliare L. JM-2256 (epiphytic herb; t; fl : Feb)Epidendrum fl exuosum G.Mey. AR-1006 (epiphytic herb; t; fl : Jun; fr: Jun)Epidendrum nocturnum Jacq. AR-1052 (epiphytic herb; t; fl : Oct)Erycina pusilla (L.) N.H.Williams et M.W.Chase AV-203, JM-2252, MR-3310, 3322 (epiphytic herb; t; fl : Dec; fr: Feb, Jun)Gongora unicolor Schltr. AV-053, JM-2204 (epiphytic herb; t; fl : Feb)Leochilus scriptus (Scheidw.) Rchb.f. AR-885 (epiphytic herb; t; fl : Dec)Maxillaria aciantha Rchb.f. AR-825, 884, JM-2258 (epiphytic herb; t; fl : Feb, Dec)

Maxillaria crassifolia (Lindl.) Rchb.f. JM-2091 (epiphytic herb; t; fr: Feb)Maxillaria hedwigae Hamer et Dodson AR-824, 831, 862, AV-052, MR-3552 (epiphytic herb; t; fl : Feb, Dec; fr: Feb)Maxillaria macleei Bateman ex Lindl. AR-833 (epiphytic herb; t; fl : Dec)Maxillaria tenuifolia Lindl. AR-981, MR-3443 (epiphytic herb; t; fl : Jun)Maxillaria variabilis Bateman ex Lindl. AR-832, 859, JM-2262, MR-3309 (epiphytic herb; t; fl : Feb, Dec)Mesadenella petenensis (L.O.Williams) Garay AR-921, AV-050, EM-37423, 3553 (herb; t; fl : Feb, Mar)Mormolyca ringens (Lindl.) Schltr. AV-161, JM-2251, 2253, 2257 (epiphytic herb; t; fl : Feb)Nidema boothii (Lindl.) Schltr. AV-239, JM-2186, 2237, 2244 (epiphytic herb; t; fl : Aug; fr: Feb)Notylia aff. barkeri Lindl. MR-3500 (epiphytic herb; s; fl : Feb)Notylia trisepala Lindl. et Paxton JM-2273 (epiphytic herb; t; fl : Feb)Oncidium sphacelatum Lindl. AR-861, 958, JM-2255 (epiphytic herb; t; fl : Feb, Apr; fr: Dec)Platystele stenostachya (Rchb.f.) Garay AR-850bis, AV-051, 122, 154, MR-3354 (epiphytic herb; t; fl : Dec, Feb)Polystachya cerea Lindl. AR-836, 1051, 1064, 1065, JM-2191 (epiphytic herb; t; fl : Oct, Nov; fr: Dec, Feb)Sarcoglottis sceptrodes (Rchb.f.) Schltr. AV-171, MR-3584 (herb; t; fl : Feb)Scaphyglottis fasciculata Hook. JM-2254 (epiphytic herb; t; fr: Feb)Specklinia marginata (Lindl.) Pridgeon et M.W.Chase AR-988, MR-3441 (epiphytic herb; t; fl : Jun)Specklinia pisinna (Luer) R.Solano et Soto Arenas AR-989, 1031, MR-3405 (epiphytic herb; t; fl : Jun, Aug)Specklinia tribuloides (Sw.) Pridgeon et M.W.Chase AR-1030, AV-054 (epiphytic herb; t; fl : Aug; fr: Feb)Stelis aff. rubens Schltr. AR-862bis (epiphytic herb; t)Trichocentrum ascendens (Lindl.) M.W.Chase et N.H.Williams MR-3494 (epiphytic herb; t)Trichosalpinx ciliaris (Lindl.) Luer AR-055, 1071 (epiphytic herb; t; fl : Nov, Feb)Tropidia polystachya Ames JM-2184, LO-013 (herb; t; fl : Nov; fr: Feb)

PoaceaeCoix lacryma-jobi L. AV-003, JM-2089, MR-3338 (herb; t; fr: Feb)Eragrostis hypnoides (Lam.) Britton, Sterns et Poggenb. AV-183 (herb; t)Guadua longifolia (E.Fourn.) R.W.Pohl JM-2178 (herb; b)

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Gynerium sagittatum (Aubl.) P.Beauv. JM-2214 (herb; b; fl : Feb; fr: Feb)Lasiacis divaricata (L.) Hitchc. AV-132 (herb; t; fr: Dec)Lasiacis ruscifolia Hitchc. var. ruscifolia JM-2167 (climbing herb; s; fr: Feb)Oplismenus compositus (L.) P.Beauv. AR-922, AV-074, 273 (herb; t; fl : Feb)Orthoclada laxa Beauved AR-1059 (herb; t)Paspalum conjugatum Bergius MR-3379 (herb; t)Paspalum paniculatum L. MR-3380bis (herb; t)Pharus latifolius L. LO-002, MR-3456 (herb; t, s; fl : Aug, Oct; fr: Oct)Pharus mezii Prodan MR-3339 (herb; t)Rhipidocladum bartlettii (McClure) McClure AV-269 (climbing herb; t; fr: Feb)Setaria parvifl ora (Poir.) Kerguelen MR-3377 (herb; t; fl : Apr)Streptochaeta spicata Schrad. ex Nees LO-005 (herb; s)

ZingiberaceaeRenealmia mexicana Klotzch ex Petersen LO-008, MR-3330, 3458 (herb; t, s; fl : Aug; fr: Feb, Aug, Oct)

MAGNOLIOPSIDAAcanthaceaeAphelandra scabra (Vahl) Sm. AR-897, AV-126, 156, EM-37421, JM-2240, MR-3466, 3480 (shrub; t; fl : Feb, Aug, Oct, Dec; fr: Feb, Mar)Barleria oenotheroides Dum.Cours. AR-912, AV-063, JM-2181, MR-3371 (herb; t, s; fl : Feb)Blechum pyramidatum (Lam.) Urb. JM-2175, MR-3374 (herb; s; fl : Feb, Apr; fr: Feb)Bravaisia integerrima (Spreng.) Standl. EM-37460 (tree; t; fl : Mar)Justicia brevifl ora (Nees) Rusby EM-37442, MR-3372, 3401 (shrub; t; fl : Feb, Mar, Apr)Justicia chol T.F.Daniell AV-290 (herb; s; fl : Feb)Odontonema tubaeforme (Bertol.) Kuntze EM-37456, MR-3422bis (herb; t; fl : Mar, Jun)Pseuderanthemum praecox (Benth.) Leonard MR-3378, 3442 (herb; t, s; fl : Apr, Jun)Ruellia nudifl ora (Engelm. et A.Gray) Urb. JM-2176, MR-3321, 3398 (herb; s; fl : Dec, Feb, Apr)Ruellia pereducta Standl. ex Lundell AR-953, JM-2229, MR-3351 (herb; t, s; fl : Feb, Apr)

ActinidiaceaeSaurauia yasicae Loes. AR-1012, AV-231, 256 (tree; t; fl : Aug)

AmaranthaceaeAmaranthus spinosus L. AV-176 (herb; b; fl : Apr)Chamissoa altissima (Jacq.) Kunth AR-977, AV-280, 282, EM-37431, MR-3360, 3403 (shrub; t, s; fl : Feb, Apr; fr: Mar, Apr)Iresine arbuscula Uline et W.L.Bray AR-933, AV-199, EM-37452 (tree; t; fl : Mar, Apr; fr: Jun)Iresine diffusa Humb. et Bonpl. ex Willd. AV-267, 302, MR-3400, 3540 (herb; s; fl : Feb, Apr; fr: Apr)

AnacardiaceaeAstronium graveolens Jacq. AR-938, 943, EM-37438 (tree; t; fl : Apr; fr: Mar)Mangifera indica L. AR-931, AV-140 (tree; fl : Feb; fr: Apr)Spondias mombin L. AR-940, 1060, AV-112 (tree; t; fl : Apr, May; fr: Nov)Toxicodendron striatum (Ruiz et Pavón) Kuntze AV-095, 157, MR-3395 (tree; t; fl : Feb)

AnnonaceaeAnnona muricata L. MR-3498 (tree; t; fr: Feb)Annona primigenia Standl. et Steyerm. AR-1018, AV-101 (tree; t; fl : Aug)Annona reticulata L. AR-930, AV-042, 296, EM-37450 (tree; t; fr: Feb, Mar, Apr, Nov)Cymbopetalum mayanum Lundell MR-3347 (tree; t; fr: Feb)Cymbopetalum pendulifl orum (Dunal) Baill. AV-100, EM-37475 (tree; t; fr: Mar)Malmea depressa (Baill.) R.E.Fr. AV-103, MR-3356 (tree; t; fr: Feb, Mar)Oxandra guatemalensis Lundell AV-190, 206 (tree; t; fl : Apr)

ApocynaceaeAspidosperma megalocarpon Mart. AR-1005 (tree; t; fl : Jun; fr: Jun)Aspidosperma spruceanum Benth. ex Müll. Arg. AR-962 (tree; t; fl : Apr; fr: Apr)Plumeria rubra L. MR-3396 (tree; t; fl : Apr)Stemmadenia donnell-smithii (Rose) Woodson AR-871, 889, AV-198, 200, 291, MR-3450 (tree; t; fl : Jun; fr: Feb, Jun, Aug, Dec)Tabernaemontana alba Mill. AV-222 (tree; t; fr: Jun)Thevetia ahouai (L.) A.DC. AR-1011, MR-3440 (tree; t; fr: Jun, Aug)

AraliaceaeDendropanax arboreus (L.) Decne. et Planch. Obs-JM-02 (tree; t)Dendropanax sp. AV-229, 233 (tree; t, s; fl : Aug; fr: Aug)

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Oreopanax obtusifolius L.O.Williams AR-855, 917, EM-37466 (epiphytic tree; t; fr: Dec, Feb, Mar)

AsclepiadaceaeMatelea gentlei (Lundell et Standl.) Woodson MR-3478 (climbing herb; t; fl : Oct; fr: Oct)Matelea velutina (Schltdl.) Woodson AV-321 (climbing herb; t; fl : Feb)

AsteraceaeBidens alba DC. var. radiata (Sch.Bip.) R.E.Ballard AR-920, AV-300, MR-3399 (herb; s; fl : Feb, Apr)Bidens squarrosa Kunth JM-2172 (herb; s; fl : Feb)Calea jamaicensis (L.) L. AV-240 (climbing herb; s; fl : Aug)Critonia belizeana B.L.Turner AR-891, AV-049, JM-2075 (shrub; t; fl : Feb)Critonia morifolia (Mill.) R.M.King et H.Rob. EM-37415 (tree; t; fl : Mar)Cyanthillum cinereum (L.) H.Rob. AV-304, JM-2166 (herb; s; fl : Feb)Chromolaena odorata (L.) R.M.King et H.Rob. AV-299, 310.3 (shrub; s; fl : Feb)Egletes liebmannii Sch.Bip. var. yucatana Shinners AV-186 (herb; t; fl : Apr)Hebeclinium macrophyllum (L.) DC. AV-310.1 (herb; t; fl : Feb)Koanophyllon galeottii (B.L.Rob.) R.M.King et H.Rob. EM-37458 (tree; t; fl : Mar)Koanophyllon pittieri (Klatt) R.M.King et H.Rob. AR-908, AV-094, JM-2243, MR-3367, 3389 (tree; t; fl : Feb; fr: Apr)Lasianthaea fruticosa (L.) K.M.Becker MR-3578 (herb; s; fl : Feb)Mikania leiostachya Benth. AV-039, 048, JM-2202, MR-3334, 3386 (liana; t; fl : Nov, Feb, Apr)Montanoa atriplicifolia Sch.Bip. AR-887, AV-274 (shrub; s; fl : Feb)Otopappus scaber S.F.Blake AR-1053, AV-160, MR-3317 (climbing herb; t, s; fl : Oct; fr: Oct, Feb)Parthenium hysterophorus L. MR-3416bis (herb; t; fl : Apr)Piptocarpha chontalensis Baker MR-3385 (liana; t; fr: Apr)Porophyllum punctatum S.F.Blake AV-247 (herb; t; fl : Aug; fr: Aug)Pseudelephantopus spicatus (B.Juss. ex Aubl.) C.F.Baker AV-264 (herb; s; fl : Feb)Sinclairia deamii Rydb. AR-936, 947, EM-37418, MR-3363, 3410 (shrub; t, s; fl : Feb, Mar, Apr; fr: Apr)Sphagneticola trilobata (L.) Pruski JM-2168 (herb; s; fl : Feb)Synedrella nodifl ora (L.) Gaertn. JM-2174 (herb; s; fl : Feb)

BegoniaceaeBegonia heracleifolia Schltdl. et Cham. AR-967, AV-308, JM-2081 (herb; s; fl : Feb, Apr; fr: Apr)

BignoniaceaeAmphitecna apiculata A.H.Gentry EM-37432, JM-2085, MR-3561 (tree; t, s; fl : Feb; fr: Feb, Mar)Amphitecna steyermarkii (A.H.Gentry) A.H.Gentry JM-2241 (tree; t; fl : Feb)Arrabidaea patellifera (Schltdl.) Sandwith AR-848 (liana; t; fl : Dec)Arrabidaea podopogon (DC.) A.H.Gentry AR-987 (liana; t; fl : Jun)Arrabidaea verrucosa (Standl.) A.H.Gentry MR-3469 (liana; t; fl : Aug)Ceratophytum tetragonolobum Sprague et Sandwith AR-973 (liana; t; fl : Apr)Cydista diversifolia (Kunth) Miers MR-3557 (liana; t)Cydista potosina (K.Schum. et Loes.) Loes. AV-224 (liana; r; fl : Jun)Paragonia pyramidata Bureau AR-900, MR-3558 (liana; t; fr: Feb)Parmentiera aculeata (Kunth) Seem. AV-213, EM-37477, MR-3513 (tree; t, s; fl : Mar, Jun; fr: Feb, Mar)Tynanthus guatemalensis Donn.Sm. AR-992, 215 (liana; t; fl : Jun)

BixaceaeBixa orellana L. AV-144 (tree; t; fr: Feb)

BombacaceaeCeiba pentandra (L.) Gaertn. AR-879 (tree; t; fl : Dec; fr: Dec)Ceiba schottii Britten et Baker f. AV-241 (tree; t; fl : Aug)Pachira aquatica Aubl. AR-1048, 1048bis (tree; t; fr: Oct)Pseudobombax ellipticum (Kunth) Dugand AR-924, AR-972, AV-096, 174m, EM-37469 (tree; t; fl : Feb, Mar, Apr)Quararibea funebris (La Llave) Vischer AR-1050, AV-227, 230, 232 (tree; t; fr: Aug, Oct; fr: Aug)Quararibea lacandonensis Alverson (sp. nov. ined.) AR-1001 (tree; r; fl : Jun)Quararibea sp. AV-194, 204, 205, JM-2270 (tree; s; fl : Jun)

BoraginaceaeBourreria andrieuxii (DC.) Hemsl. AR-1017 (tree; s; fl : Aug; fr: Aug)Cordia diversifolia DC. AR-997 (tree; t; fl : Jun)Cordia stellifera I.M.Johnst. AR-944, EM-37444 (tree; t, s; fl : Mar; fr: Apr)

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Heliotropium procumbens Mill. AV-177 (herb; t; fl : Apr)Tournefortia umbellata Kunth AV-214 (liana; t; fl : Jun)

BurseraceaeBursera simaruba (L.) Sarg. AR-870, 925, 937, AV-091, LO-010 (tree; t; fl : Apr; fr: Nov, Dec, Feb)Protium copal (Schltdl. et Cham.) Engl. AV-102, EM-37470, MR-3358, 3406, 3424 (tree; t, s; fl : Feb, Mar; fr: Mar, Jun)Protium correae D.M.Porter MR-3345 (tree; t; fr: Feb)Protium multiramifl orum Lundell AR-1063, AV-026, 115, 147, MR-3346 (tree; t, s; fr: Jun, Oct, Nov)

CactaceaeEpiphyllum hookeri Haw. AV-252, MR-3496 (epiphytic herb; s; fl : Aug, Nov)Pseudorhipsalis ramulosa (Salm-Dyck) Barthlott EM-37454 (epiphytic herb; t; fr: Mar)Rhipsalis baccifera (J.Miller) Stearn AR-866 (epiphytic herb; t; fr: Dec)Selenicereus testudo (Karw. ex Zucc.) Buxb. Obs-EM-03 (epiphytic herb; t)

CampanulaceaeLobelia berlandieri A.DC. AV-189 (herb; b; fl : Apr)Lobelia xalapensis Kunth JM-2177 (herb; s; fl : Feb)

CapparaceaeCapparis quiriguensis Standl. AR-903, 926, 927, 1000, AV-058, 069, 228, EM-37433, MR-3419 (tree; t; fl : Feb, Mar, Apr; fr: Feb, Apr, Jun, Aug)Forchhammeria trifoliata Radlk. var. trifoliata AV-143, EM-37451 (tree; t; fr: Feb, Mar)

CaricaceaeCarica papaya L. AV-248, MR-3370 (tree; t; fl : Aug; fr: Feb)

CecropiaceaeCecropia obtusifolia Bertol. Obs-EM-04 (tree; s)Cecropia peltata L. AV-047, MR-3324 (tree; t, v)Coussapoa oligocephala Donn.Sm. AV-216, MR-3455 (epiphytic tree; t; fl : Jun, Aug)

ClusiaceaeCalophyllum brasiliense Cambess. AV-168, EM-37417 (tree; t; fr: Feb, Mar)Clusia chanekiana Lundell AR-869, AV-192, JM-2082 (epiphytic tree; t, s; fl : Dec, Feb; fr: Feb, Jun, Dec)

Garcinia macrophylla Mart. AR-928, 1067, AV-262, JM-2095 (tree; t, s; fr: Feb, Apr, Nov)

CombretaceaeCombretum fruticosum Kunth AV-271 (liana; t; fl : Feb)Combretum laxum Jacq. AR-843 (liana; t; fr: Dec)Terminalia amazonia (Gmel.) Exell Obs-JM-03 (tree; t)Terminalia catappa L. MR-3525 (tree; t)

ConnaraceaeCnestidium rufescens Planch. AV-323, JM-2235 (liana; t)

ConvolvulaceaeIpomoea purpurea (L.) Roth EM-37434 (climbing herb; t; fl : Mar)Ipomoea quamoclit L. JM-2159 (climbing herb; s; fl : Feb)Ipomoea sepacuitensis Donn.Sm. AV-318 (climbing herb; t; fl : Feb)Ipomoea variabilis (Schltdl. et Cham.) Choisy AR-945, JM-2173 (climbing herb; s; fl : Feb, Mar)Merremia umbellata (L.) Hallier EM-37435, JM-2158, 2171, MR-3510 (climbing herb; t, s; fl : Feb, Mar)

CucurbitaceaeCionosicyos excisus (Griseb.) C.Jeffrey AV-059 (climbing herb; t; fl : Feb; fr: Feb)Melothria scabra Naudin AV-284, MR-3563 (climbing herb; s; fl : Feb; fr: Feb)Rytidostylis gracilis Hook. et Arn. JM-2225 (climbing herb; t; fl : Feb; fr: Feb)Sicydium tamnifolium (Kunth) Cong. MR-3362, 3369, 3408, 3533 (climbing herb; t, s; fl : Feb, Apr; fr: Feb, Apr)

ChrysobalanaceaeHirtella americana L. AR-955, 964 (tree; t; fl : Apr)Licania platypus Fritsch AR-1023 (tree; t; fl : Aug)

DilleniaceaeDavilla kunthii A.St.-Hil. AV-314, MR-3424bis (liana; t; fr: Feb)Tetracera volubilis L. ssp. volubilis AR-1070, MR-3487, 3524 (liana; t, s; fl : Oct, Nov)

EbenaceaeDiospyros yatesiana Standl. MR-3583 (tree; t; fr: Feb)

ElaeocarpaceaeMuntingia calabura L. MR-3425, 3457 (tree; t; fl : Jun, Aug; fr: Aug)

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EuphorbiaceaeAcalypha diversifolia Jacq. AR-946, AV-114, EM-37446, LO-004 (shrub; t, s; fl : Mar, Apr; fr: May)Acalypha setosa A.Rich. AV-327 (herb; t)Adelia barbinervis Schltr. et Cham. AV-028, 266, EM-37453 (tree; t; fl : Oct; fr: Feb, Mar)Alchornea latifolia Sw. AR-939, 941, AV-295, EM-37472 (tree; t; fl : Feb, Mar, Apr)Cnidoscolus multilobus (Pax) I.M.Johnst. AV-097 (shrub; t; fl : Feb; fr: Feb)Croton nitens Sw. AV-277 (tree; t; fr: Feb)Croton schiedeanus Schltdl. AV-107, EM-37416 (tree; t; fl : Mar, May)Dalechampia cissifolia Poepp. et Endl. MR-3565 (climbing herb; s; fl : Feb; fr: Feb)Dalechampia tiliifolia Lam. AV-268 (climbing herb; t; fl : Feb; fr: Feb)Drypetes brownii Standl. Obs-EM-05 (tree; t)Drypetes laterifl ora (Sw.) Krug et Urb. AV-117, EM-37420 (tree; t; fr: Jun)Euphorbia heterophylla L. JM-2169, MR-3328 (herb; t, s; fl : Feb)Euphorbia hyssopifolia L. AV-179, MR-3329 (herb; t, s; fl : Apr; fr: Apr)Euphorbia lasiocarpa G.Klotz. AV-303 (herb; t; fl : Feb; fr: Feb)Jatropha curcas L. AV-226 (tree; t; fr: Aug)Mabea occidentalis Benth. AV-001, 001bis, JM-2208 (tree; t; fl : Feb, Oct; fr: Feb, Oct)Sapium laterifl orum Hemsl. AR-1015, AV-253 (tree; t; fr: Aug)Sebastiania longicuspis Standl. AR-984, (tree; t; fr: Jun)Tetrorchidium rotundatum Standl. JM-2226 (tree; t; fr: Feb)

FabaceaeCaesalpinoideaeBauhinia macrostachya Benth. JM-2219 (liana; t)Cassia fi stula L. AR-929 (tree; t; fr: Apr)Delonix regia (Bojer ex Hook.) Raf. AR-994 (tree; t; fl : Jun)Dialium guianense (Aubl.) Sandwith Obs-JM-01 (tree; t)Schizolobium parahyba (Vell.) S.F.Blake AR-978, AV-078 (tree; t; fl : Feb; fr: Apr)Senna hayesiana (Britton et Rose) H.S.Irwin et Barneby AV-276, EM-37449, MR-3562 (shrub; t, s; fl : Feb; fr: Feb, Mar)Senna spectabilis (DC.) H.S.Irwin et Barneby Obs-EM-13 (tree; s)

FaboideaeAeschynomene americana L. MR-3535 (herb; t; fl : Feb; fr: Feb)Dalbergia glabra Standl. AV-324 (shrub; t)Dalbergia stevensonii Standl. Obs-EM-08 (tree; t)Desmodium distortum J.F.Macbr. JM-2170, 2267 (herb; t; fl : Feb)Desmodium incanum DC. AR-918, JM-2194 (herb; t; fl : Feb)Desmodium scorpiurus (Sw.) Desv. EM-37437, JM-2164, MR-3376 (climbing herb; t; fl : Feb, Mar; fr: Mar)Diphysa americana (Mill.) M.Sousa Obs-EM-09 (tree; t)Erythrina chiapasana Krukoff AV-297 (tree; t; fl : Feb)Erythrina folkersii Krukoff et Moldenke AV-021, 149 (tree; s; fl : Feb)Lonchocarpus guatemalensis Benth. Obs-EM-11 (tree; t)Lonchocarpus punctatus Kunth AR-854 (tree; t; fr: Dec)Lonchocarpus rugosus Benth. AR-1072 (tree; t; fl : Nov)Machaerium kegelii Meisn. JM-2249 (liana; t; fr: Feb)Machaerium seemannii Benth. ex Seem. Obs-EM-12 (liana; t)Mucuna argyrophylla Standl. AV-045, MR-3519, 3554, 3574 (liana; t, s; fl : Feb; fr: Nov, Feb)Mucuna sloanei Fawc. et Rendle AV-137 (liana; t; fl : Feb)Myroxylon balsamum (L.) Harms AR-860 (tree; t; fr: Dec)Phaseolus lunatus L. AV-283 (climbing herb; t; fl : Feb; fr: Feb)Platymiscium sp. EM-37471 (tree; t; fr: Mar)Pterocarpus rohrii Vahl MR-3418 (tree; t; fl : Apr)Rhynchosia precatoria (Kunth) DC. MR-3567 (climbing herb; t; fl : Feb; fr: Feb)Rhynchosia pyramidalis Urb. EM-37429 (climbing herb; t; fr: Mar)Swartzia cubensis (Britton et P.Wilson) Standl. AV-065, EM-37457 (tree; t; fr: Mar)Teramnus labialis (L.f.) Spreng. AR-957, MR-3508 (climbing herb; t, s; fl : Feb; fr: Feb, Apr)Vatairea lundellii (Standl.) Killip EM-37461, (tree; t; fl : Mar; fr: Mar)Vigna vexillata (L.) A.Rich. MR-3373 (climbing herb; t; fl : Apr)

MimosoideaeAcacia centralis (Britton et Rose) Lundell Obs-EM-06 (tree; t)

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Acacia gentlei Standl. Obs-EM-07 (tree; t)Acacia polyphylla DC. EM-37468 (tree; t; fr: Mar)Acacia usumacintensis Lundell AR-823, 881 (tree; t; fr: Dec)Calliandra emarginata (Kunth) Benth. AV-153 (shrub; t; fl : Feb; fr: Feb)Calliandra tergemina (L.) Benth. AR-1040, JM-2239, MR-3423 (tree; t; fl : Feb, Jun, Aug; fr: Jun)Cojoba arborea (L.) Britton et Rose AV-092, 254, EM-37428 (tree; t; fl : Mar; fr: Feb, Aug)Inga belizensis Standl. AR-942, 1019 (tree; t; fl : Aug; fr: Apr)Inga oerstediana Benth. ex Seem. Obs-EM-10 (tree; t)Inga pavoniana G.Don JM-2269 (tree; t)Inga vera Willd. MR-3391, 3517 (tree; t)Mimosa ervendbergii A.Gray AV-163 (liana; t; fr: Feb)Mimosa pigra L. AV-174, 223 (shrub; t; fl : Apr; fr: Jun)Zapoteca portoricensis (Jacq.) H.M.Hern. JM-2227 (shrub; t; fr: Feb)

FlacourtiaceaeCasearia nitida (L.) Jacq. AR-893 (tree; t; fr: Feb)Casearia sylvestris Sw. JM-2217 (tree; t; fl : Feb)Laetia thamnia L. AR-954, 1039, MR-3465 (tree; t; fl : Apr; fr: Aug)Zuelania guidonia Britton et Millsp. AR-970 (tree; t; fl : Apr)

GentianaceaeVoyria parasitica (Schltdl. et Cham.) Ruyters et Maas AV-123, MR-3483 (herb; t; fl : Oct, Dec)Voyria tenella Hook. AV-128 (herb; t; fl : Dec)

GesneriaceaeDrymonia serrulata (Jacq.) Mart. AR-1032 (climbing herb; s; fl : Aug)Kohleria spicata (Kunth) Oerst. JM-2265 (herb; s; fl : Feb)

LamiaceaeSalvia occidentalis Sw. JM-2160 (herb; s; fl : Feb)

LauraceaeCinnamomum trinerve (Lundell) Kosterm. AR-830, AV-242 (tree; t; fl : Aug; fr: Dec)Licaria caudata (Lundell) Kosterm. AR-1058, AV-320 (tree; t; fl : Feb; fr: Feb, Nov)

Licaria peckii (I.M.Johnst.) Kosterm. AV-210, EM-37459 (tree; t; fr: Mar)Nectandra martinicensis Mez AR-996, 1022, 1061, 1062, AV-196, MR-3485 (tree; t; fl : Jun, Aug; fr: Aug, Oct, Nov)Nectandra reticulata (Ruiz et Pav.) Mez AV-142, JM-2195 (tree; t; fl : Feb)Nectandra salicifolia (Kunth) Nees AR-986, 991 (tree; t; fl : Jun)Ocotea cernua (Nees) Mez AR-951 (tree; t; fl : Apr)Persea aff. schiedeana Nees AV-139 (tree; t; fl : Feb; fr: Feb)Persea americana Mill. AR-934, 999 (tree; t; fl : Apr; fr: Jun)

LoganiaceaeStrychnos tabascana Sprague et Sandwith JM-2234 (liana; t)

LoranthaceaeOryctanthus cordifolius (C.Presl) Urb. AV-158, MR-3393 (epiphytic shrub; t; fl : Feb, Apr; fr: Feb)

MalpighiaceaeBunchosia guatemalensis Nied. MR-3431 (tree; t; fl : Jun)Bunchosia lindeniana A.Juss. AR-990, 1009, JM-2192, LO-017, MR-3451, 3486 (tree; t; fl : Aug; fr: Feb, Jun, Aug, Oct, Nov)Bunchosia swartziana Griseb. AR-982 (tree; t; fr: Jun)Malpighia glabra L. AV-225, JM-2079, MR-3551 (tree; t, s; fl : Feb; fr: Feb, Jun)Mascagnia hiraea Fawc. et Rendle AR-980 (liana; t)Mascagnia vacciniifolia Nied. EM-37473 (liana; t; fl : Mar)Stigmaphyllon lindenianum A.Juss. MR-3522, 3577 (liana; t, s; fl : Feb)Tetrapterys discolor (G.Mey.) DC. EM-37463 (liana; t; fl : Mar)Tetrapterys glabrifolia Small AV-270 (liana; s; fr: Feb)

MalvaceaeHampea rovirosae Standl. AV-136, MR-3518, 3554bis (tree; t, s; fr: Feb)Malvaviscus arboreus Cav. var. mexicanus Schltdl. AR-904, MR-3511, 3580 (tree; t, s, b; fl : Feb; fr: Feb)Malvaviscus pendulifl orus DC. AR-886, AV-188 (shrub; b; fl : Feb, Apr)Sida acuta Burm.f. AR-822 (herb; s; fl : Dec)Sida haenkeana C.Presl JM-2161, MR-3375 (herb; s; fl : Feb, Apr)Sida rhombifolia L. AV-265 (herb; s)

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MelastomataceaeClidemia dentata D.Don AV-151, JM-2207, 2242, MR-3495 (shrub; t; fl : Feb; fr: Feb)Miconia cf. laevigata (L.) D.Don JM-2076, MR-3355, 3459 (shrub; t; fl : Feb)Miconia impetiolaris (Sw.) D.Don ex DC. AV-084, JM-2198 (tree; t; fl : Feb)Mouriri myrtilloides (Sw.) Poir. AV-104, MR-3337 (tree; t; fr: Feb, Mar)

MeliaceaeCedrela odorata L. AR-867, 911, 1014, 1045, 1046, AV-193, MR-3438 (tree; t; fl : Feb, Aug; fr: Jun, Aug, Dec)Guarea excelsa Kunth MR-3390bis, 3429 (tree; t, s; fl : Apr; fr: Jun)Guarea glabra Vahl AV-089 (tree; t; fl : Feb)Swietenia macrophylla King AR-963, 1029, 1066 (tree; t; fl : Apr; fr: Aug)Trichilia erythrocarpa Lundell AR-882, 1035, 1047, AV-040, 081, 263, 298, EM-37465, MR- 3532 (tree; t; fl : Feb, Oct, Nov, Dec; fr: Feb, Aug)Trichilia minutifl ora Standl. AR-913, AV-167, 316, MR-3422 (tree; t; fl : Feb; fr: Jun)Trichilia pallida Sw. AR-1013, 1024, AV-197, EM-37448, 37474, MR-3476 (tree; t; fl : Mar, Jun; fr: Aug, Oct)

MenispermaceaeAbuta chiapasensis Krukoff et Barneby MR-3550 (liana; t)

MoraceaeArtocarpus altilis (Parkinson) Fosberg MR-3530, 3560 (tree; s; fl : Feb)Brosimum alicastrum Sw. AR-872, AV-070, MR-3543 (tree; t; fl : Feb; fr: Dec)Brosimum lactescens (S.Moore) C.C.Berg AR-1069 (tree; t)Brosimum guianense (Aubl.) Huber Obs-EM-14 (tree; t)Castilla elastica Sessé AR-948, 998 (tree; t; fr: Jun)Dorstenia contrajerva L. AV-235, 243 (herb; t; fl : Aug)Ficus glabrata Kunth AR-974, AV-217, 301 (tree; t; fl : Apr, Jun; fr: Feb, Apr)Ficus insipida Willd. AR-899, MR-3308 (tree; t; fr: Feb)Ficus isophlebia Standl. AR-868 (tree; t; fr: Dec)Ficus trigonata L. AR-910 (tree; t; fr: Feb)Maclura tinctoria (L.) D.Don ex Steud. AV-207 (tree; t; fl : Jun)Pseudolmedia oxyphyllaria Donn.Sm. Obs-EM-15 (tree; t)

Pseudolmedia spuria (Sw.) Griseb. EM-37439, MR-3402, 3414 (tree; t; fl : Mar; fr: Apr)Trophis racemosa Urb. AV-000, JM-2080, 2086 (tree; t; fl : Feb; fr: Feb)

MyristacaceaeCompsoneura sprucei (A.DC.) Warb. Obs-JM-05 (tree; t)

MyrsinaceaeArdisia paschalis Donn.Sm. AR-898, 993, 1010, AV-085, 119, 121, JM-2245, MR-3473, 3488 (tree; t, s; fl : Jun; fr: Feb, Aug, Oct, Nov, Dec)Parathesis chiapensis Fernald JM-2218 (shrub; t; fr: Feb)

MyrtaceaeEugenia capuli (Schltdl. et Cham.) Hook. et Arn. var. lindeniana (O.Berg) Lundell MR-3582 (tree; t; fr: Feb)Eugenia octopleura Krug et Urb. JM-2248 (tree; t)Pimenta dioica (L.) Merr JM-2247 (tree; t)

NyctaginaceaeGuapira linearibracteata (Heimerl) Lundell EM-37467 (tree; t)Mirabilis jalapa L. AR-1049, AV-202, 275, MR-3449 (herb; s; fl : Feb, Jun, Aug, Oct)Neea psychotrioides Donn.Sm. MR-3464 (shrub; t; fr: Aug)Pisonia aculeata L. var. aculeata JM-2206, MR-3555 (liana; t, s; fl : Feb)

OchnaceaeOuratea lucens (Kunth) Engl. AV-106 (tree; t; fl : Mar)Ouratea nitida Kuntze AR-959, JM-2074, 2238 (tree; t; fl : Feb; fr: Apr)

OleaceaeChionanthus oblanceolatus (B.L.Rob.) P.S.Green AV-014, 071, 087, EM-37464, JM-2088, 2090, MR-3503 (tree; t; fl : Feb; fr: Feb, Mar, Oct)

OnagraceaeLudwigia leptocarpa (Nutt.) H.Hara AV-180 (herb; b; fl : Apr; fr: Apr)Ludwigia octovalvis (Jacq.) P.H.Raven AV-211 (herb; b; fl : Jun)

OxalidaceaeOxalis frutescens L. MR-3576 (herb; s; fl : Feb)

Passifl oraceaePassifl ora coriacea Juss. MR-3527, 3569 (climbing herb; s; fr: Feb)

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Passifl ora foetida L. var. nicaraguensis Killp MR-3581 (climbing herb; t; fl : Feb)Passifl ora hahnii (E.Fourn.) Mast. JM-2216 (climbing herb; s)Passifl ora sexfl ora A.Juss. JM-2236 (climbing herb; s)

PhytolaccaceaePetiveria alliacea L. AR-1004, AV-237 (herb; t; fl : Jun, Aug)Rivina humilis L. AV-079, MR-3368, 3397, 3447, 3475, 3534 (herb; t, s; fl : Feb, Apr, Aug, Oct; fr: Feb, Apr, Oct)

PiperaceaePeperomia aff. cobana C.DC. AR-883, 894 (epiphytic herb; t; fl : Dec; fr: Dec, Feb)Peperomia collocata Trel. ex Yunck. AR-834, 864 (epiphytic herb; t; fl : Dec)Peperomia fl agitans Trel. ex Yunck. AV-129, 152 (herb; t; fl : Feb)Peperomia glandulosa C.DC. AV-133 (epiphytic herb; t)Peperomia nigropunctata Miq. AR-826, 842, 851, 852, 865, JM-2201, MR-3366 (epiphytic herb; t; fl : Dec, Feb)Peperomia obtusifolia (L.) A.Dietr. AR-828, 1056 (epiphytic herb; t; fl : Nov, Dec)Peperomia pseudopereskiifolia C.DC. AV-173, JM-2200, LO-007, MR-3383 (epiphytic herb; t; fl : Feb; fr: Feb)Peperomia quadrifolia (L.) Kunth AR-835, 919, AV-131, 155, LO-006, MR-3387 (epiphytic herb; t; fl : Dec, Feb)Piper amalago L. Obs-EM-16 (shrub; t)Piper auritum Kunth AV-033 (shrub; t; fl : Nov)Piper fraguanum Trel. AV-020, JM-2072, 2163, MR-3333, 3509 (shrub; t; fl : Oct, Feb)Piper patulum Bertol. MR-3539 (herb; t; fl : Feb)Piper peltatum L. AV-032, 305 (shrub; t; fl : Nov, Feb; fr: Feb)Piper psilorhachis C.DC. AV-008 (shrub; t; fr: Oct)Piper sanctum (Miq.) Schltdl. ex C.DC. Obs-EM-17 (shrub; t)Piper aff. subeburneum Trel. et Standl. AV-013, 017, 019, 025, MR-3359, 3439, 3544 (shrub; t; fl : Oct, Feb, Jun)Piper tuberculatum Jacq. AV-022, 278, MR-3420 (shrub; t, s; fl : Oct, Feb, Apr)Piper tuerckheimii C.DC. ex Donn.Sm. AV-018, 068, 127, JM-2197, 2231, LO-003, MR-3336 (shrub; t; fl : Oct, Feb; fr: Dec, Feb)Piper variabile C.DC. AV-309, MR-3411, 3417 (shrub; t; fl : Apr; fr: Feb, Apr)

Piper yucatanense C.DC. AV-005, 236, 238, MR-3426 (shrub; t; fl : Jun; fr: Aug, Oct)Piper yzabalanum C.DC. ex Donn.Sm. AV-138, MR-3514 (shrub; t; fl : Feb; fr: Feb)

PolygonaceaeCoccoloba acapulcensis Standl. AR-1042 (tree; t; fr: Aug)Coccoloba belizensis Standl. AV-195 (tree; t; fl : Jun)

PortulacaceaePortulaca oleracea L. AV-175 (herb; b; fl : Apr)Portulaca rubricaulis Kunth AV-221 (herb; b; fl : Jun)

RhamnaceaeGouania polygama Urb. AV-162 (liana; s; fr: Feb)

RubiaceaeAlibertia edulis (Rich.) A.Rich. ex DC. AV-257m, JM-2203, MR-3460, 3507 (tree; t; fr: Feb, Aug)Alseis yucatanensis Standl. AR-1003, AV-120, MR-3365 (tree; t, s; fl : Jun; fr: Feb)Coffea arabica L. JM-2190 (shrub; t; fr: Feb)Chiococca alba (L.) Hitchc. AR-1041 (liana; t; fl : Aug; fr: Aug)Faramea occidentalis (L.) A.Rich. AV-260, JM-2210, 2221 (tree; t; fr: Feb, Aug)Geophila cordifolia Miq. AV-072, LO-015 (herb; t, s; fl : Nov; fr: Feb)Geophila repens (L.) I.M.Johnst. AV-010, 255 (herb; t, s; fl : Aug; fr: Oct)Guettarda combsii Urb. AR-1043, AV-209, 259 (tree; t; fl : Jun; fr: Aug)Guettarda tikalana Lundell JM-2250 (tree; t)Hamelia rovirosae Wernham AR-906, 995, 1037, AV-212, 250, 293 (tree; t, s; fl : Jun, Aug; fr: Feb, Aug)Psychotria carthagenensis Jacq. AV-294 (tree; s; fr: Feb)Psychotria costivenia Griseb. MR-3452 (tree; t; fr: Aug)Psychotria chiapensis Standl. JM-2230, MR-3470, 3505 (tree; t; fl : Aug; fr: Feb)Psychotria domingensis Jacq. AV-009, 118, JM-2205, LO-009, MR-3461 (shrub; t, s; fl : Jun, Aug; fr: Oct, Nov, Feb)Psychotria horizontalis Sw. AR-983, AV-012, 023, 029, 030, 109, JM-2093, 2183, LO- 012, MR-3313, 3428 (shrub; t, s; fl : May, Jun; fr: Oct, Nov, Feb)Psychotria limonensis K.Krause AV-016, 073 (shrub; t; fr: Feb)

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PLANT DIVERSITY IN YAXCHILÁN, CHIAPAS, MEXICO

Psychotria microdon (DC.) Urb. MR-3556 (liana; t)Psychotria papantlensis (Oerst.) Hemsl. MR-3463 (shrub; t; fl : Aug)Psychotria pubescens Sw. AR-1008, AV-311, JM-2077, MR-3482 (shrub; t, s; fl : Feb, Aug, Oct; fr: Oct, Feb)Randia aculeata L. AV-315 (shrub; t; fr: Feb)Simira lancifolia (Lundell) E.Martínez et Borhidi AR-1007, MR-3490 (tree; t; fl : Aug; fr: Nov)Solenandra mexicana (A.Gray) Borhidi AR-1025 (tree; t; fl : Aug)Spermacoce tenuior L. JM-2162 (herb; s; fl : Feb)

RutaceaeCasimiroa microcarpa Lundell AV-031, JM-2185, 2228 (tree; t, s; fl : Oct; fr: Feb)Casimiroa tetrameria Millsp. Obs-EM-18 (tree; t)Zanthoxylum acuminatum Macfad. AV-325, EM-37424 (tree; t)

SalicaceaeSalix humboldtiana Willd. AR-905 (tree; r; fl : Feb)

SapindaceaeAllophylus cominia (L.) Sw. AV-098 (tree; t; fl : Feb)Blomia prisca (Standl.) Lundell AR-966.5, AV-208 (tree; s; fr: Jun)Cardiospermum grandifl orum Sw. JM-2223 (herb; t; fl : Feb; fr: Feb)Cupania belizensis Standl. JM-2233, 2268 (tree; t; fr: Feb)Cupania dentata Glaz. AR-909 (tree; t; fr: Feb)Cupania glabra Sw. AR-971 (tree; t; fr: Apr)Exothea paniculata Radlk. in Durand AR-914, MR-3353 (tree; t; fl : Feb; fr: Feb)Paullinia cururu L. AV-249 (liana; s; fr: Aug)Paullinia pinnata L. MR-3571 (liana; s; fr: Feb)Serjania atrolineata C.Wright MR-3325 (climbing herb; s)Serjania depauperata Radlk. MR-3364 (climbing herb; s; fl : Feb)Serjania goniocarpa Radlk. AV-159 (liana; s; fr: Feb)Serjania macrocarpa Standl. et Steyerm. AV-077, JM-2182, MR-3342 (liana; t, s; fl : Feb)Serjania mexicana (L.) Willd. EM-37440 (liana; t; fl : Mar; fr: Mar)Serjania yucatanensis Standl. AV-169 (liana; s; fl : Feb)

SapotaceaeChrysophyllum mexicanum Brandegee ex Standl. JM-2274 (tree; t)Chrysophyllum venezuelanense (Pierre) T.D.Penn. AR-849, 1068 (tree; t; fr: Nov, Dec)Manilkara chicle (Pittier) Gilly AR-985, AV-105, MR-3462 (tree; t; fl : Jun, Aug)Manilkara zapota (L.) P.Royen AR-829, 829bis (tree; t; fr: Dec)Pouteria amygdalina (Standl.) Baehni AR-969 (tree; t; fl : Apr)Pouteria campechiana (Kunth) Baehni AR-949, 975, AV-201, 234, MR-3415 (tree; t; fl : Apr; fr: Apr, Jun, Aug)Pouteria durlandii (Standl.) Baehni Obs-JM-08 (tree; t)Pouteria reticulata (Engl.) Eyma Obs-JM-07 (tree; t)Pouteria sapota (Jacq.) H.E.Moore et Stearn AR-1028 (tree; t; fl : Aug)Sideroxylon fl oribundum Cordem. AR-1038, MR-3407 (tree; t; fl : Apr; fr: Aug)Sideroxylon foetidissimum Jacq. Obs-EM-19 (tree; t)

SimaroubaceaePicramnia teapensis Tul. AV-124 (tree; t; fr: Dec)Simarouba glauca DC. MR-3413 (tree; t; fr: Apr)

SolanaceaeCestrum nocturnum L. MR-3515, 3538 (tree; t; fl : Feb; fr: Feb)Cestrum racemosum Ruiz et Pav. AR-1033, AV-082 116, MR-3409 (tree; t; fl : Feb, Aug; fr: Apr, Jun)Lycianthes heteroclita Bitter JM-2215 (herb; t; fl : Feb)Physalis angulata L. AV-178 (herb; b; fl : Apr; fr: Apr)Physalis hirsuta M.Martens et Galeotti AV-181 (herb; b; fl : Apr; fr: Apr)Physalis philadelphica Lam. AV-285 (herb; s; fl : Feb; fr: Feb)Solanum adhaerens Willd. ex Roem. et Schult. AV-292, EM-37430 (shrub; t, s; fl : Feb; fr: Mar)Solanum americanum Mill. AV-185, 272 (herb; t, b; fl : Feb, Apr; fr: Apr)Solanum campechiense L. AV-187 (herb; b; fl : Apr)Solanum erianthum D.Don AV-046, JM-2179 (tree; t, s; fl : Nov, Feb; fr: Nov, Feb)Solanum sp. MR-3559 (shrub; s)

SterculiaceaeByttneria aculeata (Jacq.) Jacq. AR-902, MR-3521 (liana; t; fl : Feb; fr: Feb)

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Byttneria catalpaefolia Jacq. AV-286, EM-37445, JM-2084 (liana; t; fr: Feb, Mar)Theobroma cacao L. AR-099, 950 (tree; t; fr: Feb, Apr)

TheophrastaceaeDeherainia smaragdina (Planch. ex Linden) Decne. AV-056, 125 (shrub; t; fl : Dec; fr: Dec, Feb)Jacquinia macrocarpa Cav. AV-172 (tree; s; fl : Feb; fr: Feb)

TiliaceaeCorchorus siliquosus L. MR-3421 (herb; t; fr: Apr)Heliocarpus americanus E.Watson MR-3512 (tree; t)Heliocarpus donnell-smithii Rose Obs-EM-20 (tree; s)Heliocarpus mexicanus (Turcz.) Sprague AV-080, 086 (tree; t, s; fl : Feb; fr: Feb)Luehea seemannii Triana et Planch. AV-076 (tree; t; fl : Feb)Mortoniodendron sulcatum Lundell EM-37419 (tree; t; fr: Mar)Mortoniodendron vestitum Lundell AR-1016, 1020, 1021, JM-2222 (tree; t; fl : Aug; fr: Feb)Trichospermum grewiifolium (A. Rich) Kosterm. AV-064, JM-2073 (tree; t; fr: Feb)Trichospermum mexicanum (DC.) Baill. AV-083, 134 (tree; t; fl : Dec, Feb; fr: Feb)Triumfetta galeottiana Turcz. JM-2263 (herb; t; fl : Feb; fr: Feb)

TurneraceaeErblichia odorata Seem. Obs-EM-21 (tree; t)

UlmaceaeAmpelocera hottlei Standl. Obs-JM-06 (tree; t)Celtis iguanaea (Jacq.) Sarg. JM-2232 (liana; t)

UrticaceaeMyriocarpa heterostachya Donn.Sm. AV-060, 150, EM-37425, 37426, MR-3361, 3531 (tree; t, s; fl : Feb, Mar)Myriocarpa obovata Donn.Sm. MR-3504 (tree; t; fl : Feb)

Phenax mexicanus Wedd. AV-061 (herb; t)Pilea microphylla (L.) Liebm. AV-246 (herb; s; fl : Aug; fr: Aug)Pilea pubescens Liebm. LO-014 (herb; s; fl : Nov)Urera caracasana (Jacq.) Gaudich. ex Griseb. AV-245 (shrub; t; fl : Aug; fr: Aug)Urera elata (Sw.) Griseb. AR-819 (tree; t; fl : Dec; fr: Dec)

ValerianaceaeValeriana scandens Loefl . ex L. AV-306, EM-37427, JM-2092 (climbing herb; t, s; fl : Feb, Mar; fr: Feb)

VerbenaceaeAegiphila deppeana Steud. MR-3520, 3523 (liana; t; fl : Feb)Callicarpa acuminata Kunth Obs-EM-22 (shrub; t)Lantana hirta Graham AV-184, MR-3579 (herb; b, s; fl : Feb, Apr)Petrea volubilis L. EM-37447 (liana; t; fl : Mar)Vitex gaumeri Greenm. AR-961, MR-3382 (tree; t; fl : Apr)

ViolaceaeRinorea hummelii Sprague AR-952, AV-004, JM-2078, MR-3390, 3427, 3432 (tree; t; fl : Apr, Jun; fr: Feb, Jun, Oct)

ViscaceaePhoradendron crassifolium Trel. AR-820 (epiphytic shrub; s; fr: Dec)

VitaceaeCissus biformifolia Standl. AV-258, 319, MR-3491, 3529 (liana; t, s; fl : Feb, Aug, Nov)Cissus gossypiifolia Standl. AR-847, AV-057 (liana; t, s; fr: Dec, Feb)Cissus verticillata (L.) Nicolson et C.E.Jarvis ssp. verticillata AR-878, 901, AV-281, JM-2213, MR-3548, 3570 (climbing herb; t, b, s; fl : Feb; fr: Dec, Feb)Vitis popenoei J.L.Fennell JM-2165 (liana; s; fl : Feb)Vitis tiliifolia Humb. et Bonpl. MR-3568 (liana; s; fl : Feb)

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